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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme .
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why is it considered an antibiotic ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply .
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how do antibiotics make affect in the body ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria .
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what if somebody 's allergic to penicillin , is azithromycin as strong and as effective ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g .
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what percent of my weight is due to bacteria ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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so , what would happen if someone became addicted to a antibiotic ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult .
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how does the bacteria grow immune to the antibiotics ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g .
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how about bacteria definition and classificaton ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply .
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how long have scientists known about just antibiotics alone ?
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antibiotics are a type of medicine which are used to treat bacterial infections . everyday we come into contact with thousands of bacterial cells . we are colonized with lots of different types of bacteria which live on us , and inside of us ; everywhere from the grooves of your fingerprint , to the nooks and crannies of your intestines . if you count up all of the bacteria , they actually outnumber us ( by `` us '' we mean our human cells ) about 10 to 1 . to stay healthy , we need to maintain a healthy ecosystem of bacteria , called normal flora ( not all bacteria is bad ! ) , while selectively getting rid of the harmful , “ pathogenic ” bacteria which can cause an infection . pathogenic bacteria is a relative term . some bacteria can cause illness in you no matter what . other bacteria cause illness when they wander from their normal location ( e.g . intestines ) and try to live in a new location ( e.g . bladder ) , which is what happens when you develop a urinary tract infection ( uti ) . the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply . if the bacteria are susceptible to the antibiotic , then they will stop growing or simply die . these important parts include : proteins/sugars in the bacterial wall important enzymes that make new bacterial dna or proteins when an antibiotic molecule sticks to its target , it will disable or destroy that protein or enzyme . if enough of the antibiotic is present , the bacterial cell is crippled and either stops growing ( bacterio-static effect ) or simply dies ( bacteri-cidal effect ) . just to be clear , antibiotics don ’ t affect viruses , fungi , or parasites - they only bind to bacterial cell targets so they only affect bacterial cells . in fact , they specifically target bacteria rather than human cells . how were antibiotics discovered ? back in 1928 ( right before the great depression ) , alexander fleming first discovered the antibiotic penicillin when he noticed that bacteria in his lab wouldn ’ t grow near some fungus , which had accidentally found its way into his experiments . the fungus was making a small molecule which leaked into the petri gel around it , and fleming called the stuff - “ mold juice ” . he realized that the mold juice was killing the bacteria in the area ! the next big surprise for mr. fleming came when he later found out that the fungus was the same bluish-green fungus that grows on old bread . the discovery earned him the nobel prize in 1945 , and helped humanity develop a key antibiotic which has saved countless lives . in his nobel prize acceptance speech , fleming warned the world of the dangers of misusing antibiotics . he had already noted bacteria in his lab becoming resistant to penicillin , just a few years after its discovery ! after decades of antibiotic misuse , today we find ourselves facing bacteria which has become resistant to most , if not all antibiotics . how do antibiotics work ? let 's take a look at a couple of examples of antibiotics : penicillin and azithromycin . penicillin penicillin is a fabulous antibiotic because it is n't toxic to humans at concentrations that can kill bacteria and it can kill a lot of different types of bacteria . so how does it work ? penicillin weakens the bacterial wall by : deactivating a bacterial enzyme ( transpeptidase ) that builds and repairs the bacteria wall . activating a bacterial enzyme ( autolysin ) that cuts open parts of the bacterial wall , an enzyme normally only activated when the bacteria is multiplying . in short , penicillin causes the bacteria to weaken its own cell wall ( imagine being forced to punch yourself ! ) , and prevents the bacteria from being able to repair itself . with a weak wall , water seeps in , and the bacteria swells up and explodes . azithromycin azithromycin is a broad spectrum antibiotic which is often used to treat a wide variety of infections ; everything from pneumonia to sexually transmitted diseases . so how does it work ? azithromycin prevents the bacteria from multiplying by : blocking the cell 's ability to create proteins by attaching to ribosomes in the cell . in short , azithromycin prevents bacteria from multiplying , making it much easier for the immune system to handle the infection . antibiotic development over the years , a number of antibiotics have been discovered in nature or synthesized in the lab . some antibiotics target only specific bacteria and are called “ narrow spectrum ” antibiotics , whereas other antibiotics target many types of bacteria and are called “ broad spectrum ” antibiotics . developing completely new classes of antibiotics ( as opposed to variations on existing antibiotics ) is very difficult . it ’ s easy to find chemicals that kill bacteria , but not so easy to find substances that could be used as medicines , even if researchers were given infinite resources ! researchers are basically shooting in the dark . in fact , the most recent discovery of a novel antibiotic class was in 1987 , almost 30 years ago ( silver , l. , 2011 ) ! while there are a few new antibiotics currently in development , researchers don ’ t know if they ’ ll ever become usable as medicine . this void in the discovery of new antibiotics is problematic . when a bacteria becomes resistant to a specific drug within a drug class , it gains some level of resistance to drugs within the same class . for example , if a bacteria became resistant to ampicillin , it would also have some level of resistance to other penicillin-like antibiotics .
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the body ’ s immune system responds to an infection by trying to fight and destroy the invading bacteria ! what are antibiotics ? to help the immune system , we sometimes use antibiotics , which are chemicals ( specifically a swarm of small molecules ) that enter and stick to important parts ( think of targets ) of the bacterial cell , and interfere with its ability to survive and multiply .
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my question why there was n't any production of antibiotics since 1990 ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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in the conductance example , how do you get 3.125v when calculating it , you will get 3.2v ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ .
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in the example problem , i 'm confused about the use of the variable g vs the variable s. what are the meanings of these two variables , and are they interchangeable ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel .
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what about conductance in series ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant .
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hi , if one branch of parallel circuit were to open circuit what would happen to total current ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea .
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i 'm assuming because it 's parallel ( other branches are still connected to nodes ) and current are usually divided in parallel series , the current would increase and as a result power would increase ( power = current times volt ) can you confirm ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea .
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in which situations is it more useful to use conductance intstead of resistance , when they essentially describe the same thing ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances .
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do we need to know all of the formulas to build circuits ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances .
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we want to find voltage v and the individual currents ig1 , ig2 , and ig3 , ... '' is that right ?
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in a previous article we studied parallel resistors . we derived this equation to combine parallel resistors into a single equivalent resistor , $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ this is a fairly complex expression , with $ 1/\text r $ terms embedded inside another reciprocal . there is an alternate way to approach this problem , using the concept of conductance . conductance ohm 's law , $ v = i\ , \text r $ , defines resistance as the ratio of voltage over current , $ \text r = \dfrac { v } { i } $ the term conductance is the inverse of this expression . it is the ratio of current over voltage , $ \text g = \dfrac { i } { v } $ this gives us yet another way to write ohm 's law , $ i = v\ , \text g $ the unit of conductance is the siemens , abbreviated $ \text s $ . it is named after werner von siemens , founder of the german industrial electronics and telecommunications company that bears his name . there is an s at the end of siemens even if it is singular , $ 1\ , \text { siemens } $ . you may come across an older term , the mho , used as the unit of conductance . mho is just `` ohm '' spelled backwards . that term is n't used anymore . using conductance instead of resistance for the same physical object simply emphasizes a different aspect of its behavior . resistance reduces or impedes current flow , while conductance allows current to pass through . the terms are two aspects of the same idea . a $ 100\ , \omega $ resistor is the same as a conductance of $ \dfrac { 1 } { 100\ , \omega } $ $ = 0.01 \ , \text s $ . parallel conductance in this section , we 'll repeat the analysis of parallel resistors , but this time , instead of calling each component a resistor , we will call it a conductance . the result for parallel conductance will have a strong resemblance to series resistors . here is a circuit with conductances in parallel . we will analyze this circuit using the language of conductance , and the conductance form of ohm 's law , $ i = v\ , \text g. $ the value of current $ i $ is some given constant . we do n't yet know $ v $ or how $ i $ splits up into three currents through the conductances . two things we do know are : the three conductance currents add up to $ i $ . voltage $ v $ appears across all three conductances . with just this little bit of knowledge , and the conductance form of ohm 's law , we can write these expressions : $ i = i_ { \text { g1 } } + i_ { \text { g2 } } + i_ { \text { g3 } } $ $ i_ { \text { g1 } } = v \cdot \text { g1 } \qquad i_ { \text { g2 } } = v \cdot \text { g2 } \qquad i_ { \text { g3 } } = v \cdot \text { g3 } $ this is enough to get going . combining equations : $ i = v\cdot \text { g1 } \ , +\ , v\cdot \text { g2 } \ , +\ , v\cdot \text { g3 } $ factor out the voltage term and gather the conductance values in one place : $ i = v\ , \ , ( \text { g1 } + \text { g2 } + \text { g3 } ) $ this looks just like ohm 's law for a single conductance , with the parallel conductances appearing as a sum . we conclude : for conductances in parallel , the overall conductance is the sum of the individual conductances . notice how much this looks like the formula for resistors in series . conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears . $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + \text { g3 } $ conductance example let 's solve the same circuit we did for parallel resistors , but using the new representation . this is the circuit with conductances , $ \text g = \dfrac { 1 } { \text r } $ you can try to solve this yourself before looking at the answer . we want to find voltage $ v $ and the individual currents , $ i_ { \text { g1 } } $ , $ i_ { \text { g2 } } $ , and $ i_ { \text { g3 } } $ , using the conductance form of ohm 's law , $ i = v\ , \text g $ . find $ v $ and the current through the three conductances . show that the individual currents add up to $ i $ . summary conductances in parallel combine with a simple sum . the two ways to combine parallel resistors are : $ \text g_ { \text { parallel } } = \text { g1 } + \text { g2 } + ... + \text g_\text n $ $ \text r_ { \text { parallel } } = \dfrac { 1 } { \left ( \dfrac { 1 } { \text { r1 } } +\dfrac { 1 } { \text { r2 } } + ... + \dfrac { 1 } { \text { r } _ { \text n } } \right ) } $ the sum of conductances is simpler than the `` reciprocal of reciprocals '' we came up with for parallel resistors , and there are no special-case formulas to remember . this is the main reason to introduce the concept of conductance . the reciprocals did not go away , we just did them at the beginning when we derived $ \text g $ values from the given $ \text r $ 's . using conductance represents a rearrangement of the same computation . how you choose to analyze parallel circuits , $ \text g $ or $ \text r $ , is a matter of convenience and simplicity .
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conductances in parallel are like resistances in series , they add . equivalent parallel conductances we can imagine a new conductance equivalent to the sum of the parallel conductances . it is equivalent in the sense that the same voltage appears .
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in the very 1st circuit diagram suppose there are resistors in diagonal & value of every resistor is same , how will we find equivalent resistance ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation .
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why there are 61 codons ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide .
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what happens to the mrna after translation process i.e after proteins are produced ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons .
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one , what is a tata box ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule .
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and two , what are the poly-a tails and 5 ' caps ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell .
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what happens if a mrna breaks ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology .
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will part of the protein be produced from the broken piece ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide .
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if the start codon codes for the met amino acid , then does that mean that every polypeptide chain starts with the met amino acid ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code .
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can a dna end in 3 ' and the last molecule in this end is a phosphate ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) .
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why do the number of a 's on the poly-a tail vary ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell .
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what happens if the codes match ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) .
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but the thing whic is making me confused over and over again is `` in eukaryotes why does only one gene is controlled by one operon , the second thing that i wanted to ask that , why does the intons and exons ca n't go side by side toward the cytoplasm for translation ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal .
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can there be more than three codors read during translation ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology .
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what is the difference between a protein-coding gene and a non-protein-coding gene ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript .
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how does rna polymerase distinguish between coding strand and template strand of the dna such that it `` knows '' to transcribe from the template strand ?
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overview : gene expression dna is the genetic material of all organisms on earth . when dna is transmitted from parents to children , it can determine some of the children 's characteristics ( such as their eye color or hair color ) . but how does the sequence of a dna molecule actually affect a human or other organism 's features ? for example , how did the sequence of nucleotides ( as , ts , cs , and gs ) in the dna of mendel 's pea plants determine the color of their flowers ? genes specify functional products ( such as proteins ) a dna molecule is n't just a long , boring string of nucleotides . instead , it 's divided up into functional units called genes . each gene provides instructions for a functional product , that is , a molecule needed to perform a job in the cell . in many cases , the functional product of a gene is a protein . for example , mendel 's flower color gene provides instructions for a protein that helps make colored molecules ( pigments ) in flower petals . the functional products of most known genes are proteins , or , more accurately , polypeptides . polypeptide is just another word for a chain of amino acids . although many proteins consist of a single polypeptide , some are made up of multiple polypeptides . genes that specify polypeptides are called protein-coding genes . not all genes specify polypeptides . instead , some provide instructions to build functional rna molecules , such as the transfer rnas and ribosomal rnas that play roles in translation . how does the dna sequence of a gene specify a particular protein ? many genes provide instructions for building polypeptides . how , exactly , does dna direct the construction of a polypeptide ? this process involves two major steps : transcription and translation . in transcription , the dna sequence of a gene is copied to make an rna molecule . this step is called transcription because it involves rewriting , or transcribing , the dna sequence in a similar rna `` alphabet . '' in eukaryotes , the rna molecule must undergo processing to become a mature messenger rna ( mrna ) . in translation , the sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . the name translation reflects that the nucleotide sequence of the mrna sequence must be translated into the completely different `` language '' of amino acids . thus , during expression of a protein-coding gene , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein . this directional flow of information is known as the central dogma of molecular biology . non-protein-coding genes ( genes that specify functional rnas ) are still transcribed to produce an rna , but this rna is not translated into a polypeptide . for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript . the primary transcript carries the same sequence information as the non-transcribed strand of dna , sometimes called the coding strand . however , the primary transcript and the coding strand of dna are not identical , thanks to some biochemical differences between dna and rna . one important difference is that rna molecules do not include the base thymine ( t ) . instead , they have the similar base uracil ( u ) . like thymine , uracil pairs with adenine . transcription and rna processing : eukaryotes vs. bacteria in bacteria , the primary rna transcript can directly serve as a messenger rna , or mrna . messenger rnas get their name because they act as messengers between dna and ribosomes . ribosomes are rna-and-protein structures in the cytosol where proteins are actually made . in eukaryotes ( such as humans ) , a primary transcript has to go through some extra processing steps in order to become a mature mrna . during processing , caps are added to the ends of the rna , and some pieces of it may be carefully removed in a process called splicing . these steps do not happen in bacteria . the location of transcription is also different between prokaryotes and eukaryotes . eukaryotic transcription takes place in the nucleus , where the dna is stored , while protein synthesis takes place in the cytosol . because of this , a eukaryotic mrna must be exported from the nucleus before it can be translated into a polypeptide . prokaryotic cells , on the other hand , do n't have a nucleus , so they carry out both transcription and translation in the cytosol . translation after transcription ( and , in eukaryotes , after processing ) , an mrna molecule is ready to direct protein synthesis . the process of using information in an mrna to build a polypeptide is called translation . the genetic code during translation , the nucleotide sequence of an mrna is translated into the amino acid sequence of a polypeptide . specifically , the nucleotides of the mrna are read in triplets ( groups of three ) called codons . there are $ 61 $ codons that specify amino acids . one codon is a `` start '' codon that indicates where to start translation . the start codon specifies the amino acid methionine , so most polypeptides begin with this amino acid . three other “ stop ” codons signal the end of a polypeptide . these relationships between codons and amino acids are called the genetic code . steps of translation translation takes place inside of structures known as ribosomes . ribosomes are molecular machines whose job is to build polypeptides . once a ribosome latches on to an mrna and finds the `` start '' codon , it will travel rapidly down the mrna , one codon at a time . as it goes , it will gradually build a chain of amino acids that exactly mirrors the sequence of codons in the mrna . how does the ribosome `` know '' which amino acid to add for each codon ? as it turns out , this matching is not done by the ribosome itself . instead , it depends on a group of specialized rna molecules called transfer rnas ( trnas ) . each trna has a three nucleotides sticking out at one end , which can recognize ( base-pair with ) just one or a few particular codons . at the other end , the trna carries an amino acid – specifically , the amino acid that matches those codons . there are many trnas floating around in a cell , but only a trna that matches ( base-pairs with ) the codon that 's currently being read can bind and deliver its amino acid cargo . once a trna is snugly bound to its matching codon in the ribosome , its amino acid will be added the end of the polypeptide chain . this process repeats many times , with the ribosome moving down the mrna one codon at a time . a chain of amino acids is built up one by one , with an amino acid sequence that matches the sequence of codons found in the mrna . translation ends when the ribosome reaches a stop codon and releases the polypeptide . what happens next ? once the polypeptide is finished , it may be processed or modified , combine with other polypeptides , or be shipped to a specific destination inside or outside the cell . ultimately , it will perform a specific job needed by the cell or organism – perhaps as a signaling molecule , structural element , or enzyme ! summary : dna is divided up into functional units called genes , which may specify polypeptides ( proteins and protein subunits ) or functional rnas ( such as trnas and rrnas ) . information from a gene is used to build a functional product in a process called gene expression . a gene that encodes a polypeptide is expressed in two steps . in this process , information flows from dna $ \rightarrow $ rna $ \rightarrow $ protein , a directional relationship known as the central dogma of molecular biology . transcription : one strand of the gene 's dna is copied into rna . in eukaryotes , the rna transcript must undergo additional processing steps in order to become a mature messenger rna ( mrna ) . translation : the nucleotide sequence of the mrna is decoded to specify the amino acid sequence of a polypeptide . this process occurs inside a ribosome and requires adapter molecules called trnas . during translation , the nucleotides of the mrna are read in groups of three called codons . each codon specifies a particular amino acid or a stop signal . this set of relationships is known as the genetic code .
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for either type of gene , the process of going from dna to a functional product is known as gene expression . transcription in transcription , one strand of the dna that makes up a gene , called the non-coding strand , acts as a template for the synthesis of a matching ( complementary ) rna strand by an enzyme called rna polymerase . this rna strand is the primary transcript .
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how does a ribosome distinguish between coding strand and template strand of the dna and find out that it should read the coding strand ?
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background derivatives of vector-valued functions what we 're building to a unit normal vector to a two-dimensional curve is a vector with magnitude $ 1 $ that is perpendicular to the curve at some point . typically you look for a function that gives you all possible unit normal vectors of a given curve , not just one vector . to find the unit normal vector of a two-dimensional curve , take the following steps : find the tangent vector , which requires taking the derivative of the parametric function defining the curve . rotate that tangent vector $ 90^ { \circ } $ , which involves swapping the coordinates and making one of them negative . normalize the result , which requires dividing it by its own magnitude . abstractly speaking , the result you get will look something like this : $ \displaystyle \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $ for a given tiny step along the curve , think of $ dx $ as the $ x $ -component of that step , $ dy $ as the $ y $ -component of that step , and $ ds $ as the length of that step . example : normal vectors to a sine curve consider the graph of the function $ f ( x ) = \sin ( x ) $ . imagine you want a function that gives you unit normal vectors to this curve ( perhaps because you wish to compute flux through it ) . in other words , for any point on the curve , you want to be able to give the coordinates of a vector perpendicular to that curve with magnitude $ 1 $ . this means you want an expression that can take any point on the curve , and return a vector with magnitude $ 1 $ that is perpendicular to the curve at that point . step 0 : parameterize before anything , we need to make sure our curve is in parametric form . turning a function graph into a parametric function is simple enough . we let the parameter $ t $ play the role of $ x $ : $ \displaystyle \vec { \textbf { v } } ( t ) = \left [ \begin { array } { c } t \ \sin ( t ) \end { array } \right ] $ i call this `` step $ 0 $ '' because often your curve is initially defined parametrically in the first place , so this would be given to you for free . what this means for our unit normal vector is that we will find a second vector-valued function which also takes in $ t $ , but instead of outputting points on the sine curve itself , its outputs will be unit vectors normal to the curve at the point $ \vec { \textbf { v } } ( t ) $ . step 1 : find a tangent vector when you take the derivative of the parametric function , it will give you a tangent vector to the curve : if this seems unfamiliar , consider reviewing the article on derivatives of vector-valued functions . for our example , here 's what that looks like : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } \dfrac { d } { dt } ( t ) \\ \dfrac { d } { dt } ( \sin ( t ) ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] $ for example , if you plug in $ t = \pi $ to this function , you get the following vector : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } ( \pi ) = \left [ \begin { array } { c } 1 \ \cos ( \pi ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ -1 \end { array } \right ] $ when you move this vector so that its tail sits at the point $ \vec { \textbf { v } } ( \pi ) $ , which for our sine curve is $ ( \pi , 0 ) $ , it will be tangent to the curve . step 2 : rotate this vector $ 90^\circ $ to turn a tangent vector into a normal vector , rotate it by $ 90^\circ $ . how do you do this ? swap the two components and make one of them negative : $ \displaystyle \left [ \begin { array } { c } x \ y \end { array } \right ] \rightarrow \left [ \begin { array } { c } -y \ x \end { array } \right ] $ how do you choose which component to make negative ? if you are rotating counterclockwise , make the first component negative ; if you are rotating clockwise , make the second component negative . in our example , let 's rotate the tangent vector counterclockwise so that it points up : $ \displaystyle \underbrace { \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] } { \text { normal vector } } $ step 3 : scale it to magnitude $ 1 $ great ! we have a normal vector . but to make this a unit normal vector , we must divide it by its own magnitude . in our example , the magnitude is as follows : $ \displaystyle \left|\left| \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] \right|\right| = \sqrt { \cos^2 ( t ) + 1^2 } $ therefore , our unit normal vector function $ \greene { \hat { \textbf { n } } } ( t ) $ looks like this : $ \displaystyle \greene { \hat { \textbf { n } } } ( t ) = \left [ \begin { array } { c } -\cos ( t ) / \sqrt { \cos^2 ( t ) + 1^2 } \\ 1 / \sqrt { \cos^2 ( t ) + 1^2 } \end { array } \right ] $ summary let 's generalize the steps of this example to see how they apply to any parametric curve . step 0 : make sure the curve is given parametrically step 1 : find a tangent vector to your curve by differentiating the parametric function : $ \displaystyle \dfrac { d\vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] $ step 2 : rotate this vector $ 90^\circ $ by swapping the coordinates and making one negative . $ \displaystyle \underbrace { \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] } { \text { normal vector } } $ step 3 : to make this a unit normal vector , divide it by its magnitude : $ \displaystyle \dfrac { 1 } { \sqrt { x ' ( t ) ^2 + y ' ( t ) ^2 } } \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] $ if you prefer , you can think in terms of differentials , with a tiny step along the curve being represented by the vector $ \left [ \begin { array } { c } dx \dy \end { array } \right ] $ . the magnitude of this step is $ ds = \sqrt { dx^2 + dy^2 } $ . in this terminology , you might insead write down the unit normal vector like this : $ \displaystyle \greene { \hat { \textbf { n } } } = \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $
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in our example , let 's rotate the tangent vector counterclockwise so that it points up : $ \displaystyle \underbrace { \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] } { \text { normal vector } } $ step 3 : scale it to magnitude $ 1 $ great ! we have a normal vector . but to make this a unit normal vector , we must divide it by its own magnitude .
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how to calculate a normal to a surface in 3d ?
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background derivatives of vector-valued functions what we 're building to a unit normal vector to a two-dimensional curve is a vector with magnitude $ 1 $ that is perpendicular to the curve at some point . typically you look for a function that gives you all possible unit normal vectors of a given curve , not just one vector . to find the unit normal vector of a two-dimensional curve , take the following steps : find the tangent vector , which requires taking the derivative of the parametric function defining the curve . rotate that tangent vector $ 90^ { \circ } $ , which involves swapping the coordinates and making one of them negative . normalize the result , which requires dividing it by its own magnitude . abstractly speaking , the result you get will look something like this : $ \displaystyle \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $ for a given tiny step along the curve , think of $ dx $ as the $ x $ -component of that step , $ dy $ as the $ y $ -component of that step , and $ ds $ as the length of that step . example : normal vectors to a sine curve consider the graph of the function $ f ( x ) = \sin ( x ) $ . imagine you want a function that gives you unit normal vectors to this curve ( perhaps because you wish to compute flux through it ) . in other words , for any point on the curve , you want to be able to give the coordinates of a vector perpendicular to that curve with magnitude $ 1 $ . this means you want an expression that can take any point on the curve , and return a vector with magnitude $ 1 $ that is perpendicular to the curve at that point . step 0 : parameterize before anything , we need to make sure our curve is in parametric form . turning a function graph into a parametric function is simple enough . we let the parameter $ t $ play the role of $ x $ : $ \displaystyle \vec { \textbf { v } } ( t ) = \left [ \begin { array } { c } t \ \sin ( t ) \end { array } \right ] $ i call this `` step $ 0 $ '' because often your curve is initially defined parametrically in the first place , so this would be given to you for free . what this means for our unit normal vector is that we will find a second vector-valued function which also takes in $ t $ , but instead of outputting points on the sine curve itself , its outputs will be unit vectors normal to the curve at the point $ \vec { \textbf { v } } ( t ) $ . step 1 : find a tangent vector when you take the derivative of the parametric function , it will give you a tangent vector to the curve : if this seems unfamiliar , consider reviewing the article on derivatives of vector-valued functions . for our example , here 's what that looks like : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } \dfrac { d } { dt } ( t ) \\ \dfrac { d } { dt } ( \sin ( t ) ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] $ for example , if you plug in $ t = \pi $ to this function , you get the following vector : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } ( \pi ) = \left [ \begin { array } { c } 1 \ \cos ( \pi ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ -1 \end { array } \right ] $ when you move this vector so that its tail sits at the point $ \vec { \textbf { v } } ( \pi ) $ , which for our sine curve is $ ( \pi , 0 ) $ , it will be tangent to the curve . step 2 : rotate this vector $ 90^\circ $ to turn a tangent vector into a normal vector , rotate it by $ 90^\circ $ . how do you do this ? swap the two components and make one of them negative : $ \displaystyle \left [ \begin { array } { c } x \ y \end { array } \right ] \rightarrow \left [ \begin { array } { c } -y \ x \end { array } \right ] $ how do you choose which component to make negative ? if you are rotating counterclockwise , make the first component negative ; if you are rotating clockwise , make the second component negative . in our example , let 's rotate the tangent vector counterclockwise so that it points up : $ \displaystyle \underbrace { \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] } { \text { normal vector } } $ step 3 : scale it to magnitude $ 1 $ great ! we have a normal vector . but to make this a unit normal vector , we must divide it by its own magnitude . in our example , the magnitude is as follows : $ \displaystyle \left|\left| \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] \right|\right| = \sqrt { \cos^2 ( t ) + 1^2 } $ therefore , our unit normal vector function $ \greene { \hat { \textbf { n } } } ( t ) $ looks like this : $ \displaystyle \greene { \hat { \textbf { n } } } ( t ) = \left [ \begin { array } { c } -\cos ( t ) / \sqrt { \cos^2 ( t ) + 1^2 } \\ 1 / \sqrt { \cos^2 ( t ) + 1^2 } \end { array } \right ] $ summary let 's generalize the steps of this example to see how they apply to any parametric curve . step 0 : make sure the curve is given parametrically step 1 : find a tangent vector to your curve by differentiating the parametric function : $ \displaystyle \dfrac { d\vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] $ step 2 : rotate this vector $ 90^\circ $ by swapping the coordinates and making one negative . $ \displaystyle \underbrace { \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] } { \text { normal vector } } $ step 3 : to make this a unit normal vector , divide it by its magnitude : $ \displaystyle \dfrac { 1 } { \sqrt { x ' ( t ) ^2 + y ' ( t ) ^2 } } \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] $ if you prefer , you can think in terms of differentials , with a tiny step along the curve being represented by the vector $ \left [ \begin { array } { c } dx \dy \end { array } \right ] $ . the magnitude of this step is $ ds = \sqrt { dx^2 + dy^2 } $ . in this terminology , you might insead write down the unit normal vector like this : $ \displaystyle \greene { \hat { \textbf { n } } } = \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $
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this means you want an expression that can take any point on the curve , and return a vector with magnitude $ 1 $ that is perpendicular to the curve at that point . step 0 : parameterize before anything , we need to make sure our curve is in parametric form . turning a function graph into a parametric function is simple enough .
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*how to know if we need to negate the top or the bottom ?
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background derivatives of vector-valued functions what we 're building to a unit normal vector to a two-dimensional curve is a vector with magnitude $ 1 $ that is perpendicular to the curve at some point . typically you look for a function that gives you all possible unit normal vectors of a given curve , not just one vector . to find the unit normal vector of a two-dimensional curve , take the following steps : find the tangent vector , which requires taking the derivative of the parametric function defining the curve . rotate that tangent vector $ 90^ { \circ } $ , which involves swapping the coordinates and making one of them negative . normalize the result , which requires dividing it by its own magnitude . abstractly speaking , the result you get will look something like this : $ \displaystyle \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $ for a given tiny step along the curve , think of $ dx $ as the $ x $ -component of that step , $ dy $ as the $ y $ -component of that step , and $ ds $ as the length of that step . example : normal vectors to a sine curve consider the graph of the function $ f ( x ) = \sin ( x ) $ . imagine you want a function that gives you unit normal vectors to this curve ( perhaps because you wish to compute flux through it ) . in other words , for any point on the curve , you want to be able to give the coordinates of a vector perpendicular to that curve with magnitude $ 1 $ . this means you want an expression that can take any point on the curve , and return a vector with magnitude $ 1 $ that is perpendicular to the curve at that point . step 0 : parameterize before anything , we need to make sure our curve is in parametric form . turning a function graph into a parametric function is simple enough . we let the parameter $ t $ play the role of $ x $ : $ \displaystyle \vec { \textbf { v } } ( t ) = \left [ \begin { array } { c } t \ \sin ( t ) \end { array } \right ] $ i call this `` step $ 0 $ '' because often your curve is initially defined parametrically in the first place , so this would be given to you for free . what this means for our unit normal vector is that we will find a second vector-valued function which also takes in $ t $ , but instead of outputting points on the sine curve itself , its outputs will be unit vectors normal to the curve at the point $ \vec { \textbf { v } } ( t ) $ . step 1 : find a tangent vector when you take the derivative of the parametric function , it will give you a tangent vector to the curve : if this seems unfamiliar , consider reviewing the article on derivatives of vector-valued functions . for our example , here 's what that looks like : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } \dfrac { d } { dt } ( t ) \\ \dfrac { d } { dt } ( \sin ( t ) ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] $ for example , if you plug in $ t = \pi $ to this function , you get the following vector : $ \displaystyle \dfrac { d \vec { \textbf { v } } } { dt } ( \pi ) = \left [ \begin { array } { c } 1 \ \cos ( \pi ) \end { array } \right ] = \left [ \begin { array } { c } 1 \ -1 \end { array } \right ] $ when you move this vector so that its tail sits at the point $ \vec { \textbf { v } } ( \pi ) $ , which for our sine curve is $ ( \pi , 0 ) $ , it will be tangent to the curve . step 2 : rotate this vector $ 90^\circ $ to turn a tangent vector into a normal vector , rotate it by $ 90^\circ $ . how do you do this ? swap the two components and make one of them negative : $ \displaystyle \left [ \begin { array } { c } x \ y \end { array } \right ] \rightarrow \left [ \begin { array } { c } -y \ x \end { array } \right ] $ how do you choose which component to make negative ? if you are rotating counterclockwise , make the first component negative ; if you are rotating clockwise , make the second component negative . in our example , let 's rotate the tangent vector counterclockwise so that it points up : $ \displaystyle \underbrace { \left [ \begin { array } { c } 1 \ \cos ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] } { \text { normal vector } } $ step 3 : scale it to magnitude $ 1 $ great ! we have a normal vector . but to make this a unit normal vector , we must divide it by its own magnitude . in our example , the magnitude is as follows : $ \displaystyle \left|\left| \left [ \begin { array } { c } -\cos ( t ) \ 1 \end { array } \right ] \right|\right| = \sqrt { \cos^2 ( t ) + 1^2 } $ therefore , our unit normal vector function $ \greene { \hat { \textbf { n } } } ( t ) $ looks like this : $ \displaystyle \greene { \hat { \textbf { n } } } ( t ) = \left [ \begin { array } { c } -\cos ( t ) / \sqrt { \cos^2 ( t ) + 1^2 } \\ 1 / \sqrt { \cos^2 ( t ) + 1^2 } \end { array } \right ] $ summary let 's generalize the steps of this example to see how they apply to any parametric curve . step 0 : make sure the curve is given parametrically step 1 : find a tangent vector to your curve by differentiating the parametric function : $ \displaystyle \dfrac { d\vec { \textbf { v } } } { dt } = \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] $ step 2 : rotate this vector $ 90^\circ $ by swapping the coordinates and making one negative . $ \displaystyle \underbrace { \left [ \begin { array } { c } x ' ( t ) \ y ' ( t ) \end { array } \right ] } { \text { tangent vector } } \rightarrow \underbrace { \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] } { \text { normal vector } } $ step 3 : to make this a unit normal vector , divide it by its magnitude : $ \displaystyle \dfrac { 1 } { \sqrt { x ' ( t ) ^2 + y ' ( t ) ^2 } } \left [ \begin { array } { c } -y ' ( t ) \ x ' ( t ) \end { array } \right ] $ if you prefer , you can think in terms of differentials , with a tiny step along the curve being represented by the vector $ \left [ \begin { array } { c } dx \dy \end { array } \right ] $ . the magnitude of this step is $ ds = \sqrt { dx^2 + dy^2 } $ . in this terminology , you might insead write down the unit normal vector like this : $ \displaystyle \greene { \hat { \textbf { n } } } = \dfrac { 1 } { ds } \left [ \begin { array } { c } -dy \ dx \end { array } \right ] $
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step 0 : parameterize before anything , we need to make sure our curve is in parametric form . turning a function graph into a parametric function is simple enough . we let the parameter $ t $ play the role of $ x $ : $ \displaystyle \vec { \textbf { v } } ( t ) = \left [ \begin { array } { c } t \ \sin ( t ) \end { array } \right ] $ i call this `` step $ 0 $ '' because often your curve is initially defined parametrically in the first place , so this would be given to you for free .
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the article mentioned that if the top sign is reversed , it goes anti-clockwise , and visaversa if we reverse the bottom sign , but if you do n't have a visual representation of the graph , how can you tell ?
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all of the following terms appear in this unit . the terms are arranged here in alphabetical order . anthropocene epoch — a new epoch , not formally accepted by geologists , during which our species has become the dominant force for change in the biosphere . the anthropocene marks the end of the holocene epoch , about the time of the industrial revolution , 200 years ago . artisan — a person who is skilled at a craft such as pottery or weaving . biosphere — the entire network of life on earth ; the region of earth in which living organisms can be found . capitalism — a competitive economic system in which products and production means are owned by individuals or private groups . climate change — measurable changes in the climate over long periods of time . collective learning — the ability to share , preserve , and build upon ideas over time . commerce — the large-scale buying and selling of goods and services . communications — the technologies , including speech , writing , printing , and the internet , by which people exchange information and ideas . communism — a system of government or social organization in which all property is held collectively and authorities control the distribution of property and resources . for a time in the twentieth century , communist societies in the soviet union , china , eastern europe , and east and southeast asia included almost half of the world ’ s population . competitive market — a system of exchange of goods and services based on supply and demand . energy — the capacity to do work , associated with matter and radiation . includes kinetic energy , potential energy , and chemical energy , among others . exchange networks — networks that link people , societies , and regions through the transfer of information , goods , people , and sometimes disease . all forms of collective learning work through exchange networks . fossil fuel — a carbon- based material such as coal , oil , or natural gas that can be used as an energy source . fossil fuels were originally formed when the remains of living organisms were buried and broken down by intense heat and pressure over millions of years . globalization — the expansion of exchange networks until they begin to reach across the entire world . industrialization — the transition to mechanized or more technologically advanced production methods , such as factories . industrial revolution — a period of technological innovation starting in england late in the eighteenth century that resulted in a major change in the way goods were produced , and caused a major shift in global economics . these innovations came as a result of the systematic use of fossil fuels in place of human and animal power to manufacturing , communications , and transportation . innovation — generation of a new idea , method , or product . marxism — ideologies inspired by the writings of karl marx ( 1818–1883 ) . marx argued that capitalism was the key feature of the modern world , but that capitalism created such profound inequality that it would eventually have to be abolished in a future socialist society . modern revolution — a deliberately vague label for the revolutionary transformations that have created the modern world . the modern revolution began around 1500 and ushered in the modern era of human history . monopoly — a situation in which there is only one supplier of a commodity . according to economic theory , monopolies stifle innovation because monopolists have a captive market so they do not need to worry about improving the quality or reducing the price of their products . steam engines — machines that burn coal to produce steam , used to perform mechanical work . james watt configured the first profitable one at the time of the american revolution . their use launched human society over a threshold no longer limited by the annual flow of solar energy . transportation — the technologies and methods by which people and goods are moved from place to place . methods of transportation include porters , horse-drawn wagons , cars , trains , boats , planes , and shipping containers , among many others .
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according to economic theory , monopolies stifle innovation because monopolists have a captive market so they do not need to worry about improving the quality or reducing the price of their products . steam engines — machines that burn coal to produce steam , used to perform mechanical work . james watt configured the first profitable one at the time of the american revolution .
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do you mean that in the winter months people had to limit their travel until the invention of the steam engine ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours .
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why is the basis of ramadan in qur'an and what does the act of fasting meant to symbolise ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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are the five pillars of islam similar to the tenth commandments ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers .
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if giving of alms is not indicated in the qur'an why muslim take it as one of the pillar islam ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers .
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what is the rational behind this pillar ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives .
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what does islam teach happens to the eternal soul of a muslim that does not regularly keep all 5 of these rules ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified .
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what is this type of writing called ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar .
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in the photo of the believers circling the kaaba , the exterior background seems dominated by what appear to be construction cranes ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times .
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or is mecca experiencing a vast expansion/boom ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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does the breakup of saudi arabia and iran stop the pilgramage of iranian muslims ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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what does it mean in the 1st paragraph that 'there is no god , but god ' ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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what is the significance of the order of the five pillars of islam ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified .
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in the image above , ^ what is the cube with the stripes and pattern ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours .
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what is holy about ramadan ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times .
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why do thay have to do pillgrimige at least once in ther lifes ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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is muhammad the only prophet given prominence ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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is the shahada in itself a revelation where allah revealed to muhammed that he , muhammed is to be the prophet of prominence ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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did the grand children of prophet adam travel to different countries to make indians or the british ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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what is mohammed 's status in comparison to the other prophets , and do muslims generally agree on the answer to that question ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam .
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finally , since the shahada does n't refer to other prophets , has that ever lent itself to ideological fringes who reject some or all of the preceding prophets ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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what happens if they do n't obey these pillars ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar .
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and how long has the quran been around for ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times .
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how old do we have to be to make hajj ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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how is the five pillars important to the life of adherents worldwide ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere .
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what are the characteristics of medieval islam ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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my daughter is studying the five pillars at school and part of her home work is to answer the following question , can anyone advise please-how does each of the pillars show a muslim is submitting to the will of allah ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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i 've heard that pilgrimage to mecca it 's done during the month of ramadan which is the ninth month in the islamic calendar , but the article says that pilgrimage occurs in the twelfth month of the islamic calendar , can somebody explain this nine and twelfth month issue ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers .
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is n't the fourth pillar called sawm ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times .
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what were the three religious practices one could find in mecca before muhammad 's revelations ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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how is the concept of jihad related to the five pillars of islam ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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is the word `` god '' is equal of arabic word `` allah '' , if not then why ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 .
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if i would compare the five pillars of islam with each other what could i think on to find differences and similarities between them ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 .
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what i dont understand is why there are so many muslims in the world ... can someone please explain to me why ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times .
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what happens to muslims if they do not go to mecca at least once in their lifetime ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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can anyone tell me what impact has the islamic religion had on art and architecture ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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why are the five pillars important to muslims ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere .
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the hadith describe how many principles for the accomplishment of faith ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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are n't the daily prayers or 'salat ' also called 'namaz ' ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day .
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do the different groups follow the five pillars or are there variations in the different groups ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives .
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what does the word from the 5 pillars mean ?
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almost as soon as the arab armies of islam conquered new lands , they began erecting mosques and palaces and commissioning other works of art as expressions of their faith and culture . many aspects of religious practice in islam also emerged and were codified . the religious practice of islam , which literally means `` to submit to god '' , is based on tenets that are known as the five pillars , arkan , to which all members of the islamic community , umma , should adhere . 1 . the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings . 2 . daily prayers—salat muslims are expected to pray five times a day . this does not mean that they need to attend a mosque to pray ; rather , the salat , or the daily prayer , should be recited five times a day . muslims can pray anywhere ; however , they are meant to pray towards mecca . the faithful pray by bowing several times while standing and then kneeling and touching the ground or prayer mat with their foreheads , as a symbol of their reverence and submission to allah . on friday , many muslims attend a mosque near midday to pray and to listen to a sermon , khutba . 3 . alms-giving—zakat the giving of alms is the third pillar . although not defined in the qu ’ ran , muslims believe that they are meant to share their wealth with those less fortunate in their community of believers . 4 . fasting during ramadan—saum during the holy month of ramadan , the ninth month in the islamic calendar , muslims are expected to fast from dawn to dusk . while there are exceptions made for the sick , elderly , and pregnant , all are expected to refrain from eating and drinking during daylight hours . 5 . pilgrimage to mecca—hajj all muslims who are able are required to make the pilgrimage to mecca and the surrounding holy sites at least once in their lives . pilgrimage focuses on visiting the kaaba and walking around it seven times . pilgrimage occurs in the 12th month of the islamic calendar . essay by dr. elizabeth macaulay-lewis additional resources : hajj stories from the asian art museum
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the profession of faith—the shahada the profession of faith , the shahada , is the most fundamental expression of islamic beliefs . it simply states that “ there is no god but god and muhammad is his prophet. ” it underscores the monotheistic nature of islam . it is an extremely popular phrase in arabic calligraphy and appears in numerous manuscripts and religious buildings .
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what was the name of muhammad s father ?
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overview constantinople was the center of byzantine trade and culture and was incredibly diverse . the byzantine empire had an important cultural legacy , both on the orthodox church and on the revival of greek and roman studies , which influenced the renaissance . the east-west schism in 1054 divided the christian world into the orthodox church—now the eastern orthodox church—the catholic church—now roman the catholic church . people living under the early byzantine empire saw themselves as romans , but the culture of the empire changed over the centuries . as it incorporated greek and christian culture , it transformed into a unique byzantine culture . additionally , the byzantine empire was influenced by latin , coptic , armenian , and persian cultures . later on , it was influenced by islamic cultures as well . constantinople was an extremely diverse city . its residents were multi-ethnic and multi-religious . taxes for foreign traders were the same as for residents , which was pretty unique at that time . byzantine merchants actively traded with regions in the mediterranean as well as in the east and west , including areas around the black sea , the red sea , and the indian ocean . byzantine culture the byzantine empire influenced many cultures , primarily due to its role in shaping christian orthodoxy . the modern-day eastern orthodox church is the second largest christian church in the world . orthodoxy is central to the history and societies of greece , bulgaria , russia , serbia , and other countries . byzantine architecture , particularly in religious buildings , can be found in diverse regions from egypt to russia . during the byzantine renaissance—from 867 to 1056—art and literature flourished . artists adopted a naturalistic style and complex techniques from ancient greek and roman art and mixed them with christian themes . byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians . the exodus of these people from constantinople contributed to the revival of greek and roman studies , which led to the development of the renaissance in humanism and science . byzantine emigrants also brought to western europe the better preserved and accumulated knowledge of their own greek civilization . what is the cultural legacy of the byzantine empire ? byzantine social structures a central feature of byzantine culture was orthodox christianity . byzantine society was very religious , and it held certain values in high esteem , including a respect for order and traditional hierarchies . family was at the center of society , and marriage , chastity , and celibacy were celebrated and respected . because family was so significant , women and mothers were seen as important members of the family unit , though some women joined monastic orders . although moral attitudes about women dictated that they should be secluded in segregated spaces and avoid being outspoken , in practice this was not always the case . women did have their own spaces , called gynaikonitis , where they engaged in activities like spinning and weaving , but other locations were not sharply segregated between men and women . despite some restrictions , many women had a role in public life and engaged in commercial activities . women also had the right to inherit and often had independent wealth , which was frequently in the form of a dowry . women were seen by the church as spiritually equal to their male counterparts , and they played roles in convents . noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women . she instituted policies prohibiting prostitution , creating convents , and instituting harsh punishments for rape and other forms of violence against women . the reforms also expanded divorce , child guardianship , and property ownership rights for women . eunuchs , men who had been castrated , were also an important part of byzantine society . they were able to attain high positions in the byzantine court , in part because they were regarded as trustworthy due to their inability to claim the throne and have descendents . in addition to the elite classes at the top of society , byzantine society had numerous social hierarchies among peasants , who were not a homogenous group . the lives of peasants differed greatly depending on whether they owned their own property or were dependant on private or state landowners . over time , during the fourth to sixth centuries , the number of peasants who held small parcels of land declined , and peasants were increasingly tied to particular land parcels . what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries . the byzantine iconoclasm—the destruction or prohibition of religious icons and other images or monuments for religious or political motives—ignited a major controversy that lasted for a century and widened the growing divergence between east and west . the western church remained firmly in support of the use of religious images , though the church was still unified at this time . in addition , there were other disputes , including disagreement over the the source of the holy spirit , whether leavened or unleavened bread should be used in the eucharist , and the bishop of rome 's claim to universal jurisdiction . in response , the pope in the west declared a new emperor in charlemagne , solidifying the rift and causing outrage in the east . the empire in the west became known as the holy roman empire . finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ? decline during the early middle ages , despite significant territorial losses , the byzantine empire flourished . however , during the high middle ages , the empire began to decline . it lost anatolia , which is most of modern-day turkey , during the battle of manzikert in 1071 . it also suffered a defeat against the normans in the same year . its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople . in 1453—when the ottomans conquered constantinople , renaming it istanbul—the byzantine empire came to an end .
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noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women .
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what did irene do to become notable ?
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overview constantinople was the center of byzantine trade and culture and was incredibly diverse . the byzantine empire had an important cultural legacy , both on the orthodox church and on the revival of greek and roman studies , which influenced the renaissance . the east-west schism in 1054 divided the christian world into the orthodox church—now the eastern orthodox church—the catholic church—now roman the catholic church . people living under the early byzantine empire saw themselves as romans , but the culture of the empire changed over the centuries . as it incorporated greek and christian culture , it transformed into a unique byzantine culture . additionally , the byzantine empire was influenced by latin , coptic , armenian , and persian cultures . later on , it was influenced by islamic cultures as well . constantinople was an extremely diverse city . its residents were multi-ethnic and multi-religious . taxes for foreign traders were the same as for residents , which was pretty unique at that time . byzantine merchants actively traded with regions in the mediterranean as well as in the east and west , including areas around the black sea , the red sea , and the indian ocean . byzantine culture the byzantine empire influenced many cultures , primarily due to its role in shaping christian orthodoxy . the modern-day eastern orthodox church is the second largest christian church in the world . orthodoxy is central to the history and societies of greece , bulgaria , russia , serbia , and other countries . byzantine architecture , particularly in religious buildings , can be found in diverse regions from egypt to russia . during the byzantine renaissance—from 867 to 1056—art and literature flourished . artists adopted a naturalistic style and complex techniques from ancient greek and roman art and mixed them with christian themes . byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians . the exodus of these people from constantinople contributed to the revival of greek and roman studies , which led to the development of the renaissance in humanism and science . byzantine emigrants also brought to western europe the better preserved and accumulated knowledge of their own greek civilization . what is the cultural legacy of the byzantine empire ? byzantine social structures a central feature of byzantine culture was orthodox christianity . byzantine society was very religious , and it held certain values in high esteem , including a respect for order and traditional hierarchies . family was at the center of society , and marriage , chastity , and celibacy were celebrated and respected . because family was so significant , women and mothers were seen as important members of the family unit , though some women joined monastic orders . although moral attitudes about women dictated that they should be secluded in segregated spaces and avoid being outspoken , in practice this was not always the case . women did have their own spaces , called gynaikonitis , where they engaged in activities like spinning and weaving , but other locations were not sharply segregated between men and women . despite some restrictions , many women had a role in public life and engaged in commercial activities . women also had the right to inherit and often had independent wealth , which was frequently in the form of a dowry . women were seen by the church as spiritually equal to their male counterparts , and they played roles in convents . noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women . she instituted policies prohibiting prostitution , creating convents , and instituting harsh punishments for rape and other forms of violence against women . the reforms also expanded divorce , child guardianship , and property ownership rights for women . eunuchs , men who had been castrated , were also an important part of byzantine society . they were able to attain high positions in the byzantine court , in part because they were regarded as trustworthy due to their inability to claim the throne and have descendents . in addition to the elite classes at the top of society , byzantine society had numerous social hierarchies among peasants , who were not a homogenous group . the lives of peasants differed greatly depending on whether they owned their own property or were dependant on private or state landowners . over time , during the fourth to sixth centuries , the number of peasants who held small parcels of land declined , and peasants were increasingly tied to particular land parcels . what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries . the byzantine iconoclasm—the destruction or prohibition of religious icons and other images or monuments for religious or political motives—ignited a major controversy that lasted for a century and widened the growing divergence between east and west . the western church remained firmly in support of the use of religious images , though the church was still unified at this time . in addition , there were other disputes , including disagreement over the the source of the holy spirit , whether leavened or unleavened bread should be used in the eucharist , and the bishop of rome 's claim to universal jurisdiction . in response , the pope in the west declared a new emperor in charlemagne , solidifying the rift and causing outrage in the east . the empire in the west became known as the holy roman empire . finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ? decline during the early middle ages , despite significant territorial losses , the byzantine empire flourished . however , during the high middle ages , the empire began to decline . it lost anatolia , which is most of modern-day turkey , during the battle of manzikert in 1071 . it also suffered a defeat against the normans in the same year . its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople . in 1453—when the ottomans conquered constantinople , renaming it istanbul—the byzantine empire came to an end .
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finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ?
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what was the significance of the bogomils noted in the east-west schism map ?
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overview constantinople was the center of byzantine trade and culture and was incredibly diverse . the byzantine empire had an important cultural legacy , both on the orthodox church and on the revival of greek and roman studies , which influenced the renaissance . the east-west schism in 1054 divided the christian world into the orthodox church—now the eastern orthodox church—the catholic church—now roman the catholic church . people living under the early byzantine empire saw themselves as romans , but the culture of the empire changed over the centuries . as it incorporated greek and christian culture , it transformed into a unique byzantine culture . additionally , the byzantine empire was influenced by latin , coptic , armenian , and persian cultures . later on , it was influenced by islamic cultures as well . constantinople was an extremely diverse city . its residents were multi-ethnic and multi-religious . taxes for foreign traders were the same as for residents , which was pretty unique at that time . byzantine merchants actively traded with regions in the mediterranean as well as in the east and west , including areas around the black sea , the red sea , and the indian ocean . byzantine culture the byzantine empire influenced many cultures , primarily due to its role in shaping christian orthodoxy . the modern-day eastern orthodox church is the second largest christian church in the world . orthodoxy is central to the history and societies of greece , bulgaria , russia , serbia , and other countries . byzantine architecture , particularly in religious buildings , can be found in diverse regions from egypt to russia . during the byzantine renaissance—from 867 to 1056—art and literature flourished . artists adopted a naturalistic style and complex techniques from ancient greek and roman art and mixed them with christian themes . byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians . the exodus of these people from constantinople contributed to the revival of greek and roman studies , which led to the development of the renaissance in humanism and science . byzantine emigrants also brought to western europe the better preserved and accumulated knowledge of their own greek civilization . what is the cultural legacy of the byzantine empire ? byzantine social structures a central feature of byzantine culture was orthodox christianity . byzantine society was very religious , and it held certain values in high esteem , including a respect for order and traditional hierarchies . family was at the center of society , and marriage , chastity , and celibacy were celebrated and respected . because family was so significant , women and mothers were seen as important members of the family unit , though some women joined monastic orders . although moral attitudes about women dictated that they should be secluded in segregated spaces and avoid being outspoken , in practice this was not always the case . women did have their own spaces , called gynaikonitis , where they engaged in activities like spinning and weaving , but other locations were not sharply segregated between men and women . despite some restrictions , many women had a role in public life and engaged in commercial activities . women also had the right to inherit and often had independent wealth , which was frequently in the form of a dowry . women were seen by the church as spiritually equal to their male counterparts , and they played roles in convents . noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women . she instituted policies prohibiting prostitution , creating convents , and instituting harsh punishments for rape and other forms of violence against women . the reforms also expanded divorce , child guardianship , and property ownership rights for women . eunuchs , men who had been castrated , were also an important part of byzantine society . they were able to attain high positions in the byzantine court , in part because they were regarded as trustworthy due to their inability to claim the throne and have descendents . in addition to the elite classes at the top of society , byzantine society had numerous social hierarchies among peasants , who were not a homogenous group . the lives of peasants differed greatly depending on whether they owned their own property or were dependant on private or state landowners . over time , during the fourth to sixth centuries , the number of peasants who held small parcels of land declined , and peasants were increasingly tied to particular land parcels . what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries . the byzantine iconoclasm—the destruction or prohibition of religious icons and other images or monuments for religious or political motives—ignited a major controversy that lasted for a century and widened the growing divergence between east and west . the western church remained firmly in support of the use of religious images , though the church was still unified at this time . in addition , there were other disputes , including disagreement over the the source of the holy spirit , whether leavened or unleavened bread should be used in the eucharist , and the bishop of rome 's claim to universal jurisdiction . in response , the pope in the west declared a new emperor in charlemagne , solidifying the rift and causing outrage in the east . the empire in the west became known as the holy roman empire . finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ? decline during the early middle ages , despite significant territorial losses , the byzantine empire flourished . however , during the high middle ages , the empire began to decline . it lost anatolia , which is most of modern-day turkey , during the battle of manzikert in 1071 . it also suffered a defeat against the normans in the same year . its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople . in 1453—when the ottomans conquered constantinople , renaming it istanbul—the byzantine empire came to an end .
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its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople .
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what groups constantly posed threat to the byzantines ?
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overview constantinople was the center of byzantine trade and culture and was incredibly diverse . the byzantine empire had an important cultural legacy , both on the orthodox church and on the revival of greek and roman studies , which influenced the renaissance . the east-west schism in 1054 divided the christian world into the orthodox church—now the eastern orthodox church—the catholic church—now roman the catholic church . people living under the early byzantine empire saw themselves as romans , but the culture of the empire changed over the centuries . as it incorporated greek and christian culture , it transformed into a unique byzantine culture . additionally , the byzantine empire was influenced by latin , coptic , armenian , and persian cultures . later on , it was influenced by islamic cultures as well . constantinople was an extremely diverse city . its residents were multi-ethnic and multi-religious . taxes for foreign traders were the same as for residents , which was pretty unique at that time . byzantine merchants actively traded with regions in the mediterranean as well as in the east and west , including areas around the black sea , the red sea , and the indian ocean . byzantine culture the byzantine empire influenced many cultures , primarily due to its role in shaping christian orthodoxy . the modern-day eastern orthodox church is the second largest christian church in the world . orthodoxy is central to the history and societies of greece , bulgaria , russia , serbia , and other countries . byzantine architecture , particularly in religious buildings , can be found in diverse regions from egypt to russia . during the byzantine renaissance—from 867 to 1056—art and literature flourished . artists adopted a naturalistic style and complex techniques from ancient greek and roman art and mixed them with christian themes . byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians . the exodus of these people from constantinople contributed to the revival of greek and roman studies , which led to the development of the renaissance in humanism and science . byzantine emigrants also brought to western europe the better preserved and accumulated knowledge of their own greek civilization . what is the cultural legacy of the byzantine empire ? byzantine social structures a central feature of byzantine culture was orthodox christianity . byzantine society was very religious , and it held certain values in high esteem , including a respect for order and traditional hierarchies . family was at the center of society , and marriage , chastity , and celibacy were celebrated and respected . because family was so significant , women and mothers were seen as important members of the family unit , though some women joined monastic orders . although moral attitudes about women dictated that they should be secluded in segregated spaces and avoid being outspoken , in practice this was not always the case . women did have their own spaces , called gynaikonitis , where they engaged in activities like spinning and weaving , but other locations were not sharply segregated between men and women . despite some restrictions , many women had a role in public life and engaged in commercial activities . women also had the right to inherit and often had independent wealth , which was frequently in the form of a dowry . women were seen by the church as spiritually equal to their male counterparts , and they played roles in convents . noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women . she instituted policies prohibiting prostitution , creating convents , and instituting harsh punishments for rape and other forms of violence against women . the reforms also expanded divorce , child guardianship , and property ownership rights for women . eunuchs , men who had been castrated , were also an important part of byzantine society . they were able to attain high positions in the byzantine court , in part because they were regarded as trustworthy due to their inability to claim the throne and have descendents . in addition to the elite classes at the top of society , byzantine society had numerous social hierarchies among peasants , who were not a homogenous group . the lives of peasants differed greatly depending on whether they owned their own property or were dependant on private or state landowners . over time , during the fourth to sixth centuries , the number of peasants who held small parcels of land declined , and peasants were increasingly tied to particular land parcels . what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries . the byzantine iconoclasm—the destruction or prohibition of religious icons and other images or monuments for religious or political motives—ignited a major controversy that lasted for a century and widened the growing divergence between east and west . the western church remained firmly in support of the use of religious images , though the church was still unified at this time . in addition , there were other disputes , including disagreement over the the source of the holy spirit , whether leavened or unleavened bread should be used in the eucharist , and the bishop of rome 's claim to universal jurisdiction . in response , the pope in the west declared a new emperor in charlemagne , solidifying the rift and causing outrage in the east . the empire in the west became known as the holy roman empire . finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ? decline during the early middle ages , despite significant territorial losses , the byzantine empire flourished . however , during the high middle ages , the empire began to decline . it lost anatolia , which is most of modern-day turkey , during the battle of manzikert in 1071 . it also suffered a defeat against the normans in the same year . its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople . in 1453—when the ottomans conquered constantinople , renaming it istanbul—the byzantine empire came to an end .
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what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries .
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how did theodora change the byzantine state in ways which were beneficial to women ?
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overview constantinople was the center of byzantine trade and culture and was incredibly diverse . the byzantine empire had an important cultural legacy , both on the orthodox church and on the revival of greek and roman studies , which influenced the renaissance . the east-west schism in 1054 divided the christian world into the orthodox church—now the eastern orthodox church—the catholic church—now roman the catholic church . people living under the early byzantine empire saw themselves as romans , but the culture of the empire changed over the centuries . as it incorporated greek and christian culture , it transformed into a unique byzantine culture . additionally , the byzantine empire was influenced by latin , coptic , armenian , and persian cultures . later on , it was influenced by islamic cultures as well . constantinople was an extremely diverse city . its residents were multi-ethnic and multi-religious . taxes for foreign traders were the same as for residents , which was pretty unique at that time . byzantine merchants actively traded with regions in the mediterranean as well as in the east and west , including areas around the black sea , the red sea , and the indian ocean . byzantine culture the byzantine empire influenced many cultures , primarily due to its role in shaping christian orthodoxy . the modern-day eastern orthodox church is the second largest christian church in the world . orthodoxy is central to the history and societies of greece , bulgaria , russia , serbia , and other countries . byzantine architecture , particularly in religious buildings , can be found in diverse regions from egypt to russia . during the byzantine renaissance—from 867 to 1056—art and literature flourished . artists adopted a naturalistic style and complex techniques from ancient greek and roman art and mixed them with christian themes . byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians . the exodus of these people from constantinople contributed to the revival of greek and roman studies , which led to the development of the renaissance in humanism and science . byzantine emigrants also brought to western europe the better preserved and accumulated knowledge of their own greek civilization . what is the cultural legacy of the byzantine empire ? byzantine social structures a central feature of byzantine culture was orthodox christianity . byzantine society was very religious , and it held certain values in high esteem , including a respect for order and traditional hierarchies . family was at the center of society , and marriage , chastity , and celibacy were celebrated and respected . because family was so significant , women and mothers were seen as important members of the family unit , though some women joined monastic orders . although moral attitudes about women dictated that they should be secluded in segregated spaces and avoid being outspoken , in practice this was not always the case . women did have their own spaces , called gynaikonitis , where they engaged in activities like spinning and weaving , but other locations were not sharply segregated between men and women . despite some restrictions , many women had a role in public life and engaged in commercial activities . women also had the right to inherit and often had independent wealth , which was frequently in the form of a dowry . women were seen by the church as spiritually equal to their male counterparts , and they played roles in convents . noble women also patronized monasteries . however , women could not become priests in the church or have similar high roles . among royalty , the empresses theodora—who lived from 500 to 548 ce—and irene who lived from 752 to 803 ce—were notable for their power and influence . theodora in particular is known for having influenced a series of reforms that were beneficial to women . she instituted policies prohibiting prostitution , creating convents , and instituting harsh punishments for rape and other forms of violence against women . the reforms also expanded divorce , child guardianship , and property ownership rights for women . eunuchs , men who had been castrated , were also an important part of byzantine society . they were able to attain high positions in the byzantine court , in part because they were regarded as trustworthy due to their inability to claim the throne and have descendents . in addition to the elite classes at the top of society , byzantine society had numerous social hierarchies among peasants , who were not a homogenous group . the lives of peasants differed greatly depending on whether they owned their own property or were dependant on private or state landowners . over time , during the fourth to sixth centuries , the number of peasants who held small parcels of land declined , and peasants were increasingly tied to particular land parcels . what roles did women and eunuchs play in byzantine society ? how did theodora change the byzantine state in ways which were beneficial to women ? the east-west schism by the turn of the millennium , the eastern church of the byzantine empire and the western church of rome had been gradually separating along religious fault lines for centuries . the byzantine iconoclasm—the destruction or prohibition of religious icons and other images or monuments for religious or political motives—ignited a major controversy that lasted for a century and widened the growing divergence between east and west . the western church remained firmly in support of the use of religious images , though the church was still unified at this time . in addition , there were other disputes , including disagreement over the the source of the holy spirit , whether leavened or unleavened bread should be used in the eucharist , and the bishop of rome 's claim to universal jurisdiction . in response , the pope in the west declared a new emperor in charlemagne , solidifying the rift and causing outrage in the east . the empire in the west became known as the holy roman empire . finally , 1054 ce saw the east-west schism , the formal declaration of institutional separation between east , into the orthodox church—now the eastern orthodox church—and west , into the catholic church—now the roman catholic church . how did christianity change in the period leading up to the east-west schism ? how did the byzantine empire ’ s relationship to christianity change over time ? decline during the early middle ages , despite significant territorial losses , the byzantine empire flourished . however , during the high middle ages , the empire began to decline . it lost anatolia , which is most of modern-day turkey , during the battle of manzikert in 1071 . it also suffered a defeat against the normans in the same year . its capital city was devastated during the sacking of constantinople in 1204 . even after constantinople was reconquered by the byzantines in 1261 , the empire was drastically weakened . by the fifteenth century , byzantine territory barely exceeded constantinople . in 1453—when the ottomans conquered constantinople , renaming it istanbul—the byzantine empire came to an end .
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byzantine art from this period had a strong influence on the later painters of the italian renaissance . in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 , people migrated out of constantinople . among these emigrants were many byzantine scholars and artists , including grammarians , poets , writers , musicians , astronomers , architects , artists , scribes , philosophers , scientists , politicians and theologians .
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in the period following the sacking of constantinople in 1204 and the fall of constantinople in 1453 ?
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second only to leonardo da vinci ’ s mona lisa , edvard munch ’ s the scream may be the most iconic human figure in the history of western art . its androgynous , skull-shaped head , elongated hands , wide eyes , flaring nostrils and ovoid mouth have been engrained in our collective cultural consciousness ; the swirling blue landscape and especially the fiery orange and yellow sky have engendered numerous theories regarding the scene that is depicted . like the mona lisa , the scream has been the target of dramatic thefts and recoveries , and in 2012 a version created with pastel on cardboard sold to a private collector for nearly \ $ 120,000,000 making it the second highest price achieved at that time by a painting at auction . conceived as part of munch ’ s semi-autobiographical cycle “ the frieze of life , ” the scream ’ s composition exists in four forms : the first painting , done in oil , tempera , and pastel on cardboard ( 1893 , national gallery of art , oslo ) , two pastel examples ( 1893 , munch museum , oslo and 1895 , private collection ) , and a final tempera painting ( 1910 , national gallery of art , oslo ) . munch also created a lithographic version in 1895 . the various renditions show the artist ’ s creativity and his interest in experimenting with the possibilities to be obtained across an array of media , while the work ’ s subject matter fits with munch ’ s interest at the time in themes of relationships , life , death , and dread . for all its notoriety , the scream is in fact a surprisingly simple work , in which the artist utilized a minimum of forms to achieve maximum expressiveness . it consists of three main areas : the bridge , which extends at a steep angle from the middle distance at the left to fill the foreground ; a landscape of shoreline , lake or fjord , and hills ; and the sky , which is activated with curving lines in tones of orange , yellow , red , and blue-green . foreground and background blend into one another , and the lyrical lines of the hills ripple through the sky as well . the human figures are starkly separated from this landscape by the bridge . its strict linearity provides a contrast with the shapes of the landscape and the sky . the two faceless upright figures in the background belong to the geometric precision of the bridge , while the lines of the foreground figure ’ s body , hands , and head take up the same curving shapes that dominate the background landscape . the screaming figure is thus linked through these formal means to the natural realm , which was apparently munch ’ s intention . a passage in munch ’ s diary dated january 22 , 1892 , and written in nice , contains the probable inspiration for this scene as the artist remembered it : “ i was walking along the road with two friends—the sun went down—i felt a gust of melancholy—suddenly the sky turned a bloody red . i stopped , leaned against the railing , tired to death—as the flaming skies hung like blood and sword over the blue-black fjord and the city—my friends went on—i stood there trembling with anxiety—and i felt a vast infinite scream [ tear ] through nature. ” the figure on the bridge—who may even be symbolic of munch himself—feels the cry of nature , a sound that is sensed internally rather than heard with the ears . yet , how can this sensation be conveyed in visual terms ? munch ’ s approach to the experience of synesthesia , or the union of senses ( for example the belief that one might taste a color or smell a musical note ) , results in the visual depiction of sound and emotion . as such , the scream represents a key work for the symbolist movement as well as an important inspiration for the expressionist movement of the early twentieth century . symbolist artists of diverse international backgrounds confronted questions regarding the nature of subjectivity and its visual depiction . as munch himself put it succinctly in a notebook entry on subjective vision written in 1889 , “ it is not the chair which is to be painted but what the human being has felt in relation to it. ” since the scream ’ s first appearance , many critics and scholars have attempted to determine the exact scene depicted , as well as inspirations for the screaming figure . for example , it has been asserted that the unnaturally harsh colors of the sky may have been due to volcanic dust from the eruption of krakatoa in indonesia , which produced spectacular sunsets around the world for months afterwards . this event occurred in 1883 , ten years before munch painted the first version of the scream . however , as munch ’ s journal entry—written in the south of france but recalling an evening by norway ’ s fjords also demonstrates—the scream is a work of remembered sensation rather than perceived reality . art historians have also noted the figure ’ s resemblance to a peruvian mummy that had been exhibited at the world ’ s fair in paris in 1889 ( an artifact that also inspired the symbolist painter paul gauguin ) or to another mummy displayed in florence . while such events and objects are visually plausible , the work ’ s effect on the viewer does not depend on one ’ s familiarity with a precise list of historical , naturalistic , or formal sources . rather , munch sought to express internal emotions through external forms and thereby provide a visual image for a universal human experience . essay by dr. noelle paulson additional resources : this painting on the google art project art through time : the scream munch museum , oslo short biography of the artist from the j. paul getty museum walter gibbs , '' stolen munch paintings are recovered , '' nytimes , september 1 , 2006 edvard munch , nytimes topics page
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like the mona lisa , the scream has been the target of dramatic thefts and recoveries , and in 2012 a version created with pastel on cardboard sold to a private collector for nearly \ $ 120,000,000 making it the second highest price achieved at that time by a painting at auction . conceived as part of munch ’ s semi-autobiographical cycle “ the frieze of life , ” the scream ’ s composition exists in four forms : the first painting , done in oil , tempera , and pastel on cardboard ( 1893 , national gallery of art , oslo ) , two pastel examples ( 1893 , munch museum , oslo and 1895 , private collection ) , and a final tempera painting ( 1910 , national gallery of art , oslo ) . munch also created a lithographic version in 1895 .
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was one of the versions of this painting quite small ?
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second only to leonardo da vinci ’ s mona lisa , edvard munch ’ s the scream may be the most iconic human figure in the history of western art . its androgynous , skull-shaped head , elongated hands , wide eyes , flaring nostrils and ovoid mouth have been engrained in our collective cultural consciousness ; the swirling blue landscape and especially the fiery orange and yellow sky have engendered numerous theories regarding the scene that is depicted . like the mona lisa , the scream has been the target of dramatic thefts and recoveries , and in 2012 a version created with pastel on cardboard sold to a private collector for nearly \ $ 120,000,000 making it the second highest price achieved at that time by a painting at auction . conceived as part of munch ’ s semi-autobiographical cycle “ the frieze of life , ” the scream ’ s composition exists in four forms : the first painting , done in oil , tempera , and pastel on cardboard ( 1893 , national gallery of art , oslo ) , two pastel examples ( 1893 , munch museum , oslo and 1895 , private collection ) , and a final tempera painting ( 1910 , national gallery of art , oslo ) . munch also created a lithographic version in 1895 . the various renditions show the artist ’ s creativity and his interest in experimenting with the possibilities to be obtained across an array of media , while the work ’ s subject matter fits with munch ’ s interest at the time in themes of relationships , life , death , and dread . for all its notoriety , the scream is in fact a surprisingly simple work , in which the artist utilized a minimum of forms to achieve maximum expressiveness . it consists of three main areas : the bridge , which extends at a steep angle from the middle distance at the left to fill the foreground ; a landscape of shoreline , lake or fjord , and hills ; and the sky , which is activated with curving lines in tones of orange , yellow , red , and blue-green . foreground and background blend into one another , and the lyrical lines of the hills ripple through the sky as well . the human figures are starkly separated from this landscape by the bridge . its strict linearity provides a contrast with the shapes of the landscape and the sky . the two faceless upright figures in the background belong to the geometric precision of the bridge , while the lines of the foreground figure ’ s body , hands , and head take up the same curving shapes that dominate the background landscape . the screaming figure is thus linked through these formal means to the natural realm , which was apparently munch ’ s intention . a passage in munch ’ s diary dated january 22 , 1892 , and written in nice , contains the probable inspiration for this scene as the artist remembered it : “ i was walking along the road with two friends—the sun went down—i felt a gust of melancholy—suddenly the sky turned a bloody red . i stopped , leaned against the railing , tired to death—as the flaming skies hung like blood and sword over the blue-black fjord and the city—my friends went on—i stood there trembling with anxiety—and i felt a vast infinite scream [ tear ] through nature. ” the figure on the bridge—who may even be symbolic of munch himself—feels the cry of nature , a sound that is sensed internally rather than heard with the ears . yet , how can this sensation be conveyed in visual terms ? munch ’ s approach to the experience of synesthesia , or the union of senses ( for example the belief that one might taste a color or smell a musical note ) , results in the visual depiction of sound and emotion . as such , the scream represents a key work for the symbolist movement as well as an important inspiration for the expressionist movement of the early twentieth century . symbolist artists of diverse international backgrounds confronted questions regarding the nature of subjectivity and its visual depiction . as munch himself put it succinctly in a notebook entry on subjective vision written in 1889 , “ it is not the chair which is to be painted but what the human being has felt in relation to it. ” since the scream ’ s first appearance , many critics and scholars have attempted to determine the exact scene depicted , as well as inspirations for the screaming figure . for example , it has been asserted that the unnaturally harsh colors of the sky may have been due to volcanic dust from the eruption of krakatoa in indonesia , which produced spectacular sunsets around the world for months afterwards . this event occurred in 1883 , ten years before munch painted the first version of the scream . however , as munch ’ s journal entry—written in the south of france but recalling an evening by norway ’ s fjords also demonstrates—the scream is a work of remembered sensation rather than perceived reality . art historians have also noted the figure ’ s resemblance to a peruvian mummy that had been exhibited at the world ’ s fair in paris in 1889 ( an artifact that also inspired the symbolist painter paul gauguin ) or to another mummy displayed in florence . while such events and objects are visually plausible , the work ’ s effect on the viewer does not depend on one ’ s familiarity with a precise list of historical , naturalistic , or formal sources . rather , munch sought to express internal emotions through external forms and thereby provide a visual image for a universal human experience . essay by dr. noelle paulson additional resources : this painting on the google art project art through time : the scream munch museum , oslo short biography of the artist from the j. paul getty museum walter gibbs , '' stolen munch paintings are recovered , '' nytimes , september 1 , 2006 edvard munch , nytimes topics page
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while such events and objects are visually plausible , the work ’ s effect on the viewer does not depend on one ’ s familiarity with a precise list of historical , naturalistic , or formal sources . rather , munch sought to express internal emotions through external forms and thereby provide a visual image for a universal human experience . essay by dr. noelle paulson additional resources : this painting on the google art project art through time : the scream munch museum , oslo short biography of the artist from the j. paul getty museum walter gibbs , '' stolen munch paintings are recovered , '' nytimes , september 1 , 2006 edvard munch , nytimes topics page
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were any of these `` forms '' something in the ballpark of 18 to 24 centimeters tall ?
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second only to leonardo da vinci ’ s mona lisa , edvard munch ’ s the scream may be the most iconic human figure in the history of western art . its androgynous , skull-shaped head , elongated hands , wide eyes , flaring nostrils and ovoid mouth have been engrained in our collective cultural consciousness ; the swirling blue landscape and especially the fiery orange and yellow sky have engendered numerous theories regarding the scene that is depicted . like the mona lisa , the scream has been the target of dramatic thefts and recoveries , and in 2012 a version created with pastel on cardboard sold to a private collector for nearly \ $ 120,000,000 making it the second highest price achieved at that time by a painting at auction . conceived as part of munch ’ s semi-autobiographical cycle “ the frieze of life , ” the scream ’ s composition exists in four forms : the first painting , done in oil , tempera , and pastel on cardboard ( 1893 , national gallery of art , oslo ) , two pastel examples ( 1893 , munch museum , oslo and 1895 , private collection ) , and a final tempera painting ( 1910 , national gallery of art , oslo ) . munch also created a lithographic version in 1895 . the various renditions show the artist ’ s creativity and his interest in experimenting with the possibilities to be obtained across an array of media , while the work ’ s subject matter fits with munch ’ s interest at the time in themes of relationships , life , death , and dread . for all its notoriety , the scream is in fact a surprisingly simple work , in which the artist utilized a minimum of forms to achieve maximum expressiveness . it consists of three main areas : the bridge , which extends at a steep angle from the middle distance at the left to fill the foreground ; a landscape of shoreline , lake or fjord , and hills ; and the sky , which is activated with curving lines in tones of orange , yellow , red , and blue-green . foreground and background blend into one another , and the lyrical lines of the hills ripple through the sky as well . the human figures are starkly separated from this landscape by the bridge . its strict linearity provides a contrast with the shapes of the landscape and the sky . the two faceless upright figures in the background belong to the geometric precision of the bridge , while the lines of the foreground figure ’ s body , hands , and head take up the same curving shapes that dominate the background landscape . the screaming figure is thus linked through these formal means to the natural realm , which was apparently munch ’ s intention . a passage in munch ’ s diary dated january 22 , 1892 , and written in nice , contains the probable inspiration for this scene as the artist remembered it : “ i was walking along the road with two friends—the sun went down—i felt a gust of melancholy—suddenly the sky turned a bloody red . i stopped , leaned against the railing , tired to death—as the flaming skies hung like blood and sword over the blue-black fjord and the city—my friends went on—i stood there trembling with anxiety—and i felt a vast infinite scream [ tear ] through nature. ” the figure on the bridge—who may even be symbolic of munch himself—feels the cry of nature , a sound that is sensed internally rather than heard with the ears . yet , how can this sensation be conveyed in visual terms ? munch ’ s approach to the experience of synesthesia , or the union of senses ( for example the belief that one might taste a color or smell a musical note ) , results in the visual depiction of sound and emotion . as such , the scream represents a key work for the symbolist movement as well as an important inspiration for the expressionist movement of the early twentieth century . symbolist artists of diverse international backgrounds confronted questions regarding the nature of subjectivity and its visual depiction . as munch himself put it succinctly in a notebook entry on subjective vision written in 1889 , “ it is not the chair which is to be painted but what the human being has felt in relation to it. ” since the scream ’ s first appearance , many critics and scholars have attempted to determine the exact scene depicted , as well as inspirations for the screaming figure . for example , it has been asserted that the unnaturally harsh colors of the sky may have been due to volcanic dust from the eruption of krakatoa in indonesia , which produced spectacular sunsets around the world for months afterwards . this event occurred in 1883 , ten years before munch painted the first version of the scream . however , as munch ’ s journal entry—written in the south of france but recalling an evening by norway ’ s fjords also demonstrates—the scream is a work of remembered sensation rather than perceived reality . art historians have also noted the figure ’ s resemblance to a peruvian mummy that had been exhibited at the world ’ s fair in paris in 1889 ( an artifact that also inspired the symbolist painter paul gauguin ) or to another mummy displayed in florence . while such events and objects are visually plausible , the work ’ s effect on the viewer does not depend on one ’ s familiarity with a precise list of historical , naturalistic , or formal sources . rather , munch sought to express internal emotions through external forms and thereby provide a visual image for a universal human experience . essay by dr. noelle paulson additional resources : this painting on the google art project art through time : the scream munch museum , oslo short biography of the artist from the j. paul getty museum walter gibbs , '' stolen munch paintings are recovered , '' nytimes , september 1 , 2006 edvard munch , nytimes topics page
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for example , it has been asserted that the unnaturally harsh colors of the sky may have been due to volcanic dust from the eruption of krakatoa in indonesia , which produced spectacular sunsets around the world for months afterwards . this event occurred in 1883 , ten years before munch painted the first version of the scream . however , as munch ’ s journal entry—written in the south of france but recalling an evening by norway ’ s fjords also demonstrates—the scream is a work of remembered sensation rather than perceived reality .
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how many versions of the scream are there ?
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picking up from the ancients we can see from donatello 's sculpture of david—with its careful depiction of bones and muscles and a nude figure—that the study of human anatomy was enormously important for renaissance artists . they continued where the ancient greeks and romans had left off , with an interest in creating images of the human beings where bodies moved in natural ways—in correct proportion and feeling the pull of gravity . sculptures from ancient greece and rome reveal that classical artists closely observed the human body . ancient greek and roman artists focused their attention on youthful bodies in the prime of life . ancient sources indicate these artists used models to help them study the details of the body in the way that it looked and moved . these artists tried to show their viewers that they understood systems of muscles beneath the skin . in the middle ages , there was very little interest in the human body , which was seen as only a temporary vessel for the soul . the body was seen as sinful , the cause of temptation . in the old testament , adam and eve eat the apple from the tree of knowledge , realize their nakedness , and cover themselves . due to the nudity in this important story , christians associated nudity with sin and the fall of humankind . medieval images of naked bodies do not reflect close observation from real life or an understanding of the inner workings of bodies . dissection the best way to learn human anatomy is not just to look at the outside of the body , but to study anatomy through dissection . even though the catholic church prohibited dissection , artists and scientists performed dissection to better understand the body . renaissance artists were anxious to gain specialized knowledge of the inner workings of the human body , which would allow them to paint and sculpt the body in many different positions . the artists of the early renaissance used scientific tools ( like linear perspective and the study of anatomy and geometry ) to make their art more naturalistic , more like real life . the term `` naturalism '' describes this effort . scientific naturalism allowed artists in the early renaissance to begin to demand that society think of them as more than just skilled manual laborers . they argued that their work—which was based on science and math—was a product of their intellect just as much as their hands . they wanted artists to have the same status as intellectuals and philosophers , unlike the medieval craftsmen that came before them . essay by dr. beth harris and dr. steven zucker additional resources : anatomy in the renaissance from the metropolitan humseum of art 's timeline of art history
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the term `` naturalism '' describes this effort . scientific naturalism allowed artists in the early renaissance to begin to demand that society think of them as more than just skilled manual laborers . they argued that their work—which was based on science and math—was a product of their intellect just as much as their hands .
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what city-state was renaissance born in ?
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picking up from the ancients we can see from donatello 's sculpture of david—with its careful depiction of bones and muscles and a nude figure—that the study of human anatomy was enormously important for renaissance artists . they continued where the ancient greeks and romans had left off , with an interest in creating images of the human beings where bodies moved in natural ways—in correct proportion and feeling the pull of gravity . sculptures from ancient greece and rome reveal that classical artists closely observed the human body . ancient greek and roman artists focused their attention on youthful bodies in the prime of life . ancient sources indicate these artists used models to help them study the details of the body in the way that it looked and moved . these artists tried to show their viewers that they understood systems of muscles beneath the skin . in the middle ages , there was very little interest in the human body , which was seen as only a temporary vessel for the soul . the body was seen as sinful , the cause of temptation . in the old testament , adam and eve eat the apple from the tree of knowledge , realize their nakedness , and cover themselves . due to the nudity in this important story , christians associated nudity with sin and the fall of humankind . medieval images of naked bodies do not reflect close observation from real life or an understanding of the inner workings of bodies . dissection the best way to learn human anatomy is not just to look at the outside of the body , but to study anatomy through dissection . even though the catholic church prohibited dissection , artists and scientists performed dissection to better understand the body . renaissance artists were anxious to gain specialized knowledge of the inner workings of the human body , which would allow them to paint and sculpt the body in many different positions . the artists of the early renaissance used scientific tools ( like linear perspective and the study of anatomy and geometry ) to make their art more naturalistic , more like real life . the term `` naturalism '' describes this effort . scientific naturalism allowed artists in the early renaissance to begin to demand that society think of them as more than just skilled manual laborers . they argued that their work—which was based on science and math—was a product of their intellect just as much as their hands . they wanted artists to have the same status as intellectuals and philosophers , unlike the medieval craftsmen that came before them . essay by dr. beth harris and dr. steven zucker additional resources : anatomy in the renaissance from the metropolitan humseum of art 's timeline of art history
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these artists tried to show their viewers that they understood systems of muscles beneath the skin . in the middle ages , there was very little interest in the human body , which was seen as only a temporary vessel for the soul . the body was seen as sinful , the cause of temptation .
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why was the body illegal during the mideval ages ?
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picking up from the ancients we can see from donatello 's sculpture of david—with its careful depiction of bones and muscles and a nude figure—that the study of human anatomy was enormously important for renaissance artists . they continued where the ancient greeks and romans had left off , with an interest in creating images of the human beings where bodies moved in natural ways—in correct proportion and feeling the pull of gravity . sculptures from ancient greece and rome reveal that classical artists closely observed the human body . ancient greek and roman artists focused their attention on youthful bodies in the prime of life . ancient sources indicate these artists used models to help them study the details of the body in the way that it looked and moved . these artists tried to show their viewers that they understood systems of muscles beneath the skin . in the middle ages , there was very little interest in the human body , which was seen as only a temporary vessel for the soul . the body was seen as sinful , the cause of temptation . in the old testament , adam and eve eat the apple from the tree of knowledge , realize their nakedness , and cover themselves . due to the nudity in this important story , christians associated nudity with sin and the fall of humankind . medieval images of naked bodies do not reflect close observation from real life or an understanding of the inner workings of bodies . dissection the best way to learn human anatomy is not just to look at the outside of the body , but to study anatomy through dissection . even though the catholic church prohibited dissection , artists and scientists performed dissection to better understand the body . renaissance artists were anxious to gain specialized knowledge of the inner workings of the human body , which would allow them to paint and sculpt the body in many different positions . the artists of the early renaissance used scientific tools ( like linear perspective and the study of anatomy and geometry ) to make their art more naturalistic , more like real life . the term `` naturalism '' describes this effort . scientific naturalism allowed artists in the early renaissance to begin to demand that society think of them as more than just skilled manual laborers . they argued that their work—which was based on science and math—was a product of their intellect just as much as their hands . they wanted artists to have the same status as intellectuals and philosophers , unlike the medieval craftsmen that came before them . essay by dr. beth harris and dr. steven zucker additional resources : anatomy in the renaissance from the metropolitan humseum of art 's timeline of art history
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dissection the best way to learn human anatomy is not just to look at the outside of the body , but to study anatomy through dissection . even though the catholic church prohibited dissection , artists and scientists performed dissection to better understand the body . renaissance artists were anxious to gain specialized knowledge of the inner workings of the human body , which would allow them to paint and sculpt the body in many different positions . the artists of the early renaissance used scientific tools ( like linear perspective and the study of anatomy and geometry ) to make their art more naturalistic , more like real life . the term `` naturalism '' describes this effort .
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why did artist like the body so much ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess .
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what is the chemical equation for `` just for fun '' problem ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants .
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what does ( aq ) stand for ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution .
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what is le chatelier 's principle ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun !
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may i ask , how can i identify the right precipitating reagent for sodium ( na ) ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun !
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or how can i know if that 's the right precipitating reagent in any element or analyte ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture .
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in the example , why is nano3 mentioned in the question but not used in the equation ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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what molecular weights were used to get the answers given in hint 3 , if not mols cl- = 58.44n+95.20m ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture .
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how do you reach the first equation of hint 1 ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ?
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sorry but i have another question : the statement `` it is okay if we have extra agno3 ( aq ) , since once all the cl- has reacted , the rest of the agno3 will simply stay part of the solution which we will be able to filter away '' ( this statement can be found under situation 3 : adding agno3 ( aq ) in excess , sentence line # 11 and # 12 ) , how can the excess agno3 be filtered away ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent .
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hey , can someone further explain the terms `` aqueous '' , `` insoluble '' , and `` precipitation reaction '' to me ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ .
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how are the molar masses being determined/rounded ?
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution . the chemical that is added to cause the precipitation is called the precipitant or precipitating agent . the solid precipitate can be separated from the liquid components using filtration , and the mass of the solid can be used along with the balanced chemical equation to calculate the amount or concentration of ionic compounds in solution . sometimes you might hear people referring to precipitation gravimetry simply as gravimetric analysis , which is a broader class of analytical techniques that includes precipitation gravimetry and volatilization gravimetry . if you want to read more about gravimetric analysis in general , see this article on gravimetric analysis and volatilization gravimetry . in this article , we will go through an example of finding the amount of an aqueous ionic compound using precipitation gravimetry . we will also discuss some common sources of error in our experiment , because sometimes in lab things do n't go quite as expected and it can help to be extra prepared ! example : determining the purity of a mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ oh no ! our sometimes less-than-helpful lab assistant igor mixed up the bottles of chemicals again . ( in his defense , many white crystalline solids look interchangeable , but that is why reading labels is important ! ) as a result of the mishap , we have $ 0.7209 \ , \text g $ of a mysterious mixture containing $ \text { mgcl } _2 $ and $ \text { nano } _3 $ . we would like to know the relative amount of each compound in our mixture , which is fully dissolved in water . we add an excess of our precipitating agent silver ( i ) nitrate , $ \text { agno } _3 ( aq ) $ , and observe the formation of a precipitate , $ \text { agcl } ( s ) $ . once the precipitate is filtered and dried , we find that the mass of the solid is $ 1.032 \ , \text { g } $ . what is the mass percent of $ \text { mgcl } _2 $ in the original mixture ? any gravimetric analysis calculation is really just a stoichiometry problem plus some extra steps . since this is a stoichiometry problem , we will want to start with a balanced chemical equation . here we are interested in the precipitation reaction between $ \text { mgcl } _2 ( aq ) $ and $ \text { agno } _3 ( aq ) $ to make $ \text { agcl } ( s ) $ , when $ \text { agno } _3 ( aq ) $ is in excess . you might remember that precipitation reactions are a type of double replacement reaction , which means we can predict the products by swapping the anions ( or cations ) of the reactants . we might check our solubility rules if necessary , and then balance the reaction . in this problem we are already given the identity of the precipitate , $ \text { agcl } ( s ) $ . that means we just have to identify the other product , $ \text { mg ( no } _3 ) _2 ( aq ) $ , and make sure the overall reaction is balanced . the resulting balanced chemical equation is : $ \text { mgcl } _2 ( aq ) +2\text { agno } _3 ( aq ) \rightarrow2\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) $ the balanced equation tells us that for every $ 1 \ , \text { mol mgcl } _2 ( aq ) $ , which is the compound we are interested in quantifying , we expect to make $ 2 \ , \text { mol agcl } ( s ) $ , our precipitate . we will use this molar ratio to convert moles of $ \text { agcl } ( s ) $ to moles of $ \text { mgcl } _2 ( aq ) $ . we are also going to make the following assumptions : all of the precipitate is $ \text { agcl } ( s ) $ . we do n't have to worry about any precipitate forming from the $ \text { nano } _3 $ . all of the $ \text { cl } ^- ( aq ) $ has reacted to form $ \text { agcl } ( s ) $ . in terms of the stoichiometry , we need to make sure we add an excess of the precipitating agent $ \text { agno } _3 ( aq ) $ so all of the $ \text { cl } ^- ( aq ) $ from $ \text { mgcl } _2 ( aq ) $ reacts . now let 's go through the full calculation step-by-step ! step $ 1 $ : convert mass of precipitate , $ \text { agcl } ( s ) , $ to moles since we are assuming that the mass of the precipitate is all $ \text { agcl } ( s ) $ , we can use the molecular weight of $ \text { agcl } $ to convert the mass of precipitate to moles . $ \text { mol of agcl } ( s ) =1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \text { mol agcl } } { 143.32\ , \cancel { \text { g agcl } } } =0.007201\ , \text { mol agcl } =7.201 \times 10^ { -3 } \ , \text { mol agcl } $ step $ 2 $ : convert moles of precipitate to moles of $ \text { mgcl } _2 $ we can convert the moles of $ \text { agcl } ( s ) $ , the precipitate , to moles of $ \text { mgcl } _2 ( aq ) $ using the molar ratio from the balanced equation . $ \text { mol of mgcl } _2 ( aq ) =7.201\times10^ { -3 } \ , \cancel { \text { mol agcl } } \times \dfrac { 1\ , \text { mol mgcl } _2 } { 2\ , \cancel { \text { mol agcl } } } =3.600 \times 10^ { -3 } \ , \text { mol mgcl } _2 $ step $ 3 $ : convert moles of $ \text { mgcl } _2 $ to mass in grams since we are interested in calculating the mass percent of $ \text { mgcl } _2 $ in the original mixture , we will need to convert moles of $ \text { mgcl } _2 $ into grams using the molecular weight . $ \text { mass of mgcl } _2=3.600 \times 10^ { -3 } \ , \cancel { \text { mol mgcl } _2 } \times \dfrac { 95.20 \ , \text { g mgcl } _2 } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.3427\ , \text { g mgcl } _2 $ step $ 4 $ : calculate mass percent of $ \text { mgcl } _2 $ in the original mixture the mass percent of $ \text { mgcl } _2 $ in the original mixture can be calculated using the ratio of the mass of $ \text { mgcl } _2 $ from step $ 3 $ and the mass of the mixture . $ \text { mass % mgcl } _2= \dfrac { 0.3427 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =47.54\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~~~~\text { ( thanks igor ! ) } $ shortcut : we could also combine steps $ 1 $ through $ 3 $ into a single calculation which will involve careful checking of units to make sure everything cancels out properly : $ \text { mass of mgcl } _2=\underbrace { 1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 2\ , \cancel { \text { mol agcl } } } } \times \underbrace { \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } } =0.3427\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 1 : } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { step 2 : } ~~~~~~~~~~~~~~~~~~\text { step 3 : } $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\text { find mol agcl } ~~~~~~~~~~~~~~~~~~~\text { use mole ratio } ~~~~~~\text { find g mgcl } _2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ potential sources of error we now know how to use stoichiometry to analyze the results of a precipitation gravimetry experiment . if you are doing gravimetric analysis in lab , however , you might find that there are various factors than can affect the accuracy of your experimental results ( and therefore also your calculations ) . some common complications include : lab errors , such as not fully drying the precipitate stoichiometry errors , such as not balancing the equation for the precipitation reaction or not adding $ \text { agno } _3 ( aq ) $ in excess what would happen to our results in the above situations ? situation $ 1 $ : the precipitate is not fully dried maybe you ran out of time during the lab period , or the vacuum filtration set-up was not producing sufficient vacuum . it probably does n't help that water is notoriously difficult to fully remove compared to typical organic solvents because it has a relatively high boiling point as well as a tendency to hang on with hydrogen-bonds whenever possible . let 's think about how residual water would affect our calculations . if our precipitate is not completely dry when we measure the mass , we will think we have a higher mass of $ \text { agcl } ( s ) $ than we actually do ( since we are now measuring the mass of $ \text { agcl } ( s ) $ plus the residual water ) . a higher mass of $ \text { agcl } ( s ) $ will result in calculating more moles of $ \text { agcl } ( s ) $ in step $ 1 $ , which will be converted into more moles of $ \text { mgcl } _2 ( s ) $ in our mixture . in the last step , we will end up calculating that the mass percent of $ \text { mgcl } _2 ( s ) $ is higher than it really is . lab tip : if you have time , one way to check for water in the sample is to recheck the mass a few times during the end of the drying process to make sure the mass is not changing even if you dry it longer . this is called drying to constant mass , and while it does not guarantee that your sample is completely dry , it certainly helps ! you can also try stirring up your sample during the drying process to break up clumps and increase surface area . make sure you do n't tear holes in the filter paper , though ! situation $ 2 $ : we forgot to balance the equation ! remember how we said earlier that gravimetric analysis is really just another stoichiometry problem ? that means that working from an unbalanced equation can mess up our calculations . for this scenario , we would be using stoichiometric coefficients from the following unbalanced equation : $ \text { mgcl } _2 ( aq ) +\text { agno } _3 ( aq ) \rightarrow\text { agcl } ( s ) +\text { mg ( no } _3 ) _2 ( aq ) ~~~~~~~~~~~ ( \text { \redd { warning } : not balanced } ! ) $ this equation tells us ( incorrectly ! ) that for every mole of $ \text { agcl } ( s ) $ we make , we can infer that we started with $ 1 $ mole of $ \text { mgcl } _2 $ in the original mixture . when we use that stoichiometric ratio to calculate the mass of $ \text { mgcl } _2 $ , we will get : $ \text { mass of mgcl } _2=1.032\ , \cancel { \text { g agcl } } \times \dfrac { 1\ , \cancel { \text { mol agcl } } } { 143.32\ , \cancel { \text { g agcl } } } \times \underbrace { \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { \teald { 1 } \ , \cancel { \text { mol agcl } } } } \times \dfrac { 95.20 \ , \cancel { \text { g mgcl } _2 } } { 1\ , \cancel { \text { mol mgcl } _2 } } =0.6854\ , \text { g mgcl } _2 $ $ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\teald { \text { wrong molar ratio ! } } ~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $ we just calculated that the mass of $ \text { mgcl } _2 $ in our mixture is double the correct amount ! this will result in overestimating the mass percent of $ \text { mgcl } _2 $ by a factor of $ 2 $ : $ \text { mass % mgcl } _2= \dfrac { 0.6854 \ , \text { g mgcl } _2 } { 0.7209\ , \text { g mixture } } \times100\ % =95.08\ % \ , \text { mgcl } _2\ , \text { in mixture } ~~~ ( \text { compare to 47.54 % ! ! } ) $ situation $ 3 $ : adding $ \text { agno } _3 ( aq ) $ in excess in the last scenario we wonder what would happen if we did n't add $ \text { agno } _3 ( aq ) $ in excess . we know this would be bad because if $ \text { agno } _3 ( aq ) $ is not in excess , we will have unreacted $ \text { cl } ^- $ in solution . that means the mass of $ \text { agcl } ( s ) $ will no longer be a measure of the mass of $ \text { mgcl } _2 $ in the original mixture since we wo n't be accounting for the $ \text { cl } ^- $ still in solution . therefore , we will underestimate the mass percent of $ \text { mgcl } _2 $ in the original mixture . a related and perhaps more important question we might want to answer is : how do we make sure that we are adding $ \text { agno } _3 ( aq ) $ in excess ? if we knew the answer to that question , we could be extra confident in our calculations ! in this problem : we have $ 0.7209 \ , \text g $ of a mixture that contains some percentage of $ \text { mgcl } _2 $ . we also know from our balanced equation that for each mole of $ \text { mgcl } _2 $ , we will need $ 2 $ moles of $ \text { agno } _3 ( aq ) $ at a minimum . it is okay if we have extra $ \text { agno } _3 ( aq ) $ , since once all the $ \text { cl } ^- $ has reacted , the rest of the $ \text { agno } _3 $ will simply stay part of the solution which we will be able to filter away . if we do n't know how many moles of $ \text { mgcl } _2 $ are in our original mixture , how do we calculate the number of moles of $ \text { agno } _3 $ necessary to add ? we know that the more moles of $ \text { mgcl } _2 $ we have in our original mixture , the more moles of $ \text { agno } _3 $ we need . luckily , we have enough information to prepare for the worst case scenario , which is when our mixture is $ 100\ % \ , \text { mgcl } _2 $ . this is the maximum amount of $ \text { mgcl } _2 $ we can possibly have , which means this is when we will need the most $ \text { agno } _3 $ . let 's pretend that we have $ 100\ % \ , \text { mgcl } _2 $ . how many moles of $ \text { agno } _3 $ will we need ? this is another stoichiometry problem ! we can calculate the number of moles of $ \text { agno } _3 $ by converting the mass of the sample to moles of $ \text { mgcl } _2 $ using the molecular weight , and then converting to the moles of $ \text { agno } _3 $ using the molar ratio : $ \text { mol of agno } _3=0.7209\ , \cancel { \text { g mgcl } _2 } \times \dfrac { 1\ , \cancel { \text { mol mgcl } _2 } } { 95.20\ , \cancel { \text { g mgcl } _2 } } \times \dfrac { 2\ , \text { mol agno } _3 } { 1\ , \cancel { \text { mol mgcl } _2 } } =1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ this result tells us that even if we do n't know exactly how much $ \text { mgcl } _2 $ we have in our mixture , as long as we add at least $ 1.514 \times 10^ { -2 } \ , \text { mol agno } _3 $ we should be good to go ! summary precipitation gravimetry is a gravimetric analysis technique that uses a precipitation reaction to calculate the amount or concentration of an ionic compound . for example , we could add a solution containing $ \text { ag } ^+ $ to quantify the amount of a halide ion such as $ \text { br } ^- ( aq ) $ . some useful tips for precipitation gravimetry experiments and calculations include : double check stoichiometry and make sure equations are balanced . make sure that the precipitate is dried to constant mass . add an excess of the precipitating agent . just for fun ! let 's say we started with $ 0.4015\ , \text g $ of a mixture of $ \text { mgcl } _2 $ and $ \text { nacl } $ . we add an excess of $ \text { agno } _3 ( aq ) $ and find that we have $ 1.032\ , \text g $ of the precipitate , $ \text { agcl } ( s ) $ . how many moles of $ \text { mgcl } _2 $ and $ \text { nacl } $ did we have in our original mixture ? express your answers with $ 4 $ significant digits .
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what is precipitation gravimetry ? precipitation gravimetry is an analytical technique that uses a precipitation reaction to separate ions from a solution .
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what is a salt in chemistry ?
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