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introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
in these cases , an organism 's genotype , or set of alleles , still determines its phenotype , or observable features . however , a variety of alleles may interact with one another in different ways to specify phenotype . as a side note , we 're probably lucky that mendel 's pea genes did n't show these complexities .
do heterozygous genotypes always share the trait of one of the alleles ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
a $ c^hc^h $ rabbit has himalayan ( color-point ) patterning , with a white body and dark ears , face , feet , and tail a $ cc $ rabbit is albino , with a pure white coat . multiple alleles makes for many possible dominance relationships . in this case , the black $ c $ allele is completely dominant to all the others ;...
how do you know which alleles are dominant over others and which are dominated or not dominant over others ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
however , heterozygotes ( $ l^ml^n $ ) have both types of markers in equal numbers on the cell surface . as for incomplete dominance , we can still use mendel 's rules to predict inheritance of codominant alleles . for example , if two people with $ l^ml^n $ genotypes had children , we would expect to see m , mn , and ...
why does n't mendelian inheritance apply to the inheritance of alleles that result in incomplete dominance and codominant ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
for example , self-fertilization of a pink plant would produce a genotype ratio of $ 1 $ $ c^rc^r $ $ : $ $ 2 $ $ c^rc^w $ $ : $ $ 1 $ $ c^wc^w $ and a phenotype ratio of $ 1:2:1 $ red : pink : white . alleles are still inherited according to mendel 's basic rules , even when they show incomplete dominance . codominanc...
but when do we consider the white color of a plant as a recessive trait ( and thus mating occurs according to mendel 's law ) and when does it blend with the red color and the mating then follows the rule or category of incomplete dominance ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
alleles are still inherited according to mendel 's basic rules , even when they show incomplete dominance . codominance closely related to incomplete dominance is codominance , in which both alleles are simultaneously expressed in the heterozygote . we can see an example of codominance in the mn blood groups of humans ...
what is the defining feature of codominance ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
is it that there needs to be a third allele so one could say that two dominant alleles are codominant over a single recessive allele ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
however , heterozygotes ( $ l^ml^n $ ) have both types of markers in equal numbers on the cell surface . as for incomplete dominance , we can still use mendel 's rules to predict inheritance of codominant alleles . for example , if two people with $ l^ml^n $ genotypes had children , we would expect to see m , mn , and ...
which inheritance does incomplete dominance follow , qualitive or quantitive ... ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
if they had , it ’ s possible that mendel would not have understood his results , and would n't have figured out the core principles of inheritance—which are key in helping us understand the special cases ! incomplete dominance mendel ’ s results were groundbreaking partly because they contradicted the ( then-popular )...
what are the 7 traits that are examples of incomplete dominance ?
introduction gregor mendel knew how to keep things simple . in mendel 's work on pea plants , each gene came in just two different versions , or alleles , and these alleles had a nice , clear-cut dominance relationship ( with the dominant allele fully overriding the recessive allele to determine the plant 's appearance...
codominance closely related to incomplete dominance is codominance , in which both alleles are simultaneously expressed in the heterozygote . we can see an example of codominance in the mn blood groups of humans ( less famous than the abo blood groups , but still important ! ) . a person 's mn blood type is determined ...
people with blood group ab possess which kind of antibodies ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
as we will see below , the periodic table organizes elements in a way that reflects their number and pattern of electrons , which makes it useful for predicting the reactivity of an element : how likely it is to form bonds , and with which other elements . electron shells and the bohr model an early model of the atom w...
if the bohr model is an inaccurate representation of electron 's movement , why is it so universally accepted ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
why is the table in a specific shape ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this is why third-row elements , such as argon , can be stable with just eight valence electrons : their $ s $ and $ p $ subshells are filled , even though the entire 3n shell is not . while electron shells and orbitals are closely related , orbitals provide a more accurate picture of the electron configuration of an a...
would it be possible to get a diagram of the shell 's 3d shape as displayed in the `` more on orbitals and electron configuration '' video ( @ ~5 ) on this document ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in general , atoms are most stable , least reactive , when their outermost electron shell is full . most of the elements important in biology need eight electrons in their outermost shell in order to be stable , and this rule of thumb is known as the octet rule . some atoms can be stable with an octet even though their...
how can you actually define the octet rule ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
we can break each electron shell down into one or more subshells , which are simply sets of one or more orbitals . subshells are designated by the letters $ s $ , $ p $ , $ d $ , and $ f $ , and each letter indicates a different shape . for instance , $ s $ subshells have a single , spherical orbital , while $ p $ subs...
is the elctron subshell the s , p , d and f orbitals ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this is why third-row elements , such as argon , can be stable with just eight valence electrons : their $ s $ and $ p $ subshells are filled , even though the entire 3n shell is not . while electron shells and orbitals are closely related , orbitals provide a more accurate picture of the electron configuration of an a...
and is it a probability function describing where an electron is likely to be ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
subshells $ d $ and $ f $ have more complex shapes and contain five and seven orbitals , respectively . the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital .
what 's the difference between an electron shell and subshell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
electron configurations and the periodic table elements are placed in order on the periodic table based on their atomic number , how many protons they have . in a neutral atom , the number of electrons will equal the number of protons , so we can easily determine electron number from atomic number . in addition , the p...
how can you determine the number of outer shell electrons based on the full electron configuration ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
in the second last paragraph , i do n't really get why because of the d subshell having more energy , argon is stable with 8 valence electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
we can break each electron shell down into one or more subshells , which are simply sets of one or more orbitals . subshells are designated by the letters $ s $ , $ p $ , $ d $ , and $ f $ , and each letter indicates a different shape . for instance , $ s $ subshells have a single , spherical orbital , while $ p $ subs...
why do the sub-shells ( s , p , d ) have different shapes ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
because its 2n shell is filled , it is energetically stable as a single atom and will rarely form chemical bonds with other atoms . the third electron shell , 3n , also contains an $ s $ orbital and three $ p $ orbitals , and the third-row elements of the periodic table place their electrons in these orbitals , much as...
are the p-orbitals in the 2n or 3n shells distinguishable , and if so , in what way ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
thus , group number is a good predictor of how reactive each element will be : helium ( $ \text { he } $ ) , neon ( $ \text { ne } $ ) , and argon ( $ \text { ar } $ ) , as group 18 elements , have outer electron shells that are full or satisfy the octet rule . this makes them highly stable as single atoms . because of...
do we have microscopes powerful enough to view atoms and observe this behavior or is there some other method ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
subshells $ d $ and $ f $ have more complex shapes and contain five and seven orbitals , respectively . the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital . hydrogen has just one...
in it 's first orbital , 8 in it 's second , and 18 in it 's third , what happens if you have an atom that has more than 2+8+18 electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this can be written out in a shorthand form called an electron configuration as $ 1s^ 1 $ , where the superscripted 1 refers to the one electron in the $ 1s $ orbital . helium has two electrons , so it can completely fill the $ 1s $ orbital with its two electrons . this is written out as $ 1s^ 2 $ , referring to the tw...
so does the electrons fill the 4s before 3d as 4s has less energy than 3d ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this is why third-row elements , such as argon , can be stable with just eight valence electrons : their $ s $ and $ p $ subshells are filled , even though the entire 3n shell is not . while electron shells and orbitals are closely related , orbitals provide a more accurate picture of the electron configuration of an a...
who appropriated the accurate structure of the atom ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this is why third-row elements , such as argon , can be stable with just eight valence electrons : their $ s $ and $ p $ subshells are filled , even though the entire 3n shell is not . while electron shells and orbitals are closely related , orbitals provide a more accurate picture of the electron configuration of an a...
who invented the electron shells or orbitals ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
why are elements 57-79 and 89-103 written separately in the periodic table ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the bohr model shows the atom as a central nucleus containing protons and neutrons , with the electrons in circular electron shells at specific distances from the nucleus , similar to planets orbiting around the sun . each electron shell has a different energy level , with those shells closest to the nucleus being lowe...
if an electron can wander so far away from the nucleus just because of a small blast of light waves , if a strong blast of energy hits an electron can it `` escape '' the atom entirely ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
hydrogen and helium are the only two elements that have electrons exclusively in the $ 1s $ orbital in their neutral , non-charged , state . the second electron shell , 2n , contains another spherical $ s $ orbital plus three dumbbell-shaped $ p $ orbitals , each of which can hold two electrons . after the $ 1s $ orbit...
if electrons 'fill ' from the inside out , why are `` d '' orbitals not filled before s & p ( when looking at rows four and on ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
neon ( $ \text { ne } $ ) , on the other hand , has a total of ten electrons : two are in its innermost $ 1s $ orbital and eight fill the second shell—two each in the $ 2s $ and three $ p $ orbitals , $ 1s^ 2 $ $ 2s^ 2 $ $ 2p^6 $ . because its 2n shell is filled , it is energetically stable as a single atom and will ra...
for example : why is 4s & 4p filled before 3d ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in order to move between shells , an electron must absorb or release an amount of energy corresponding exactly to the difference in energy between the shells . for instance , if an electron absorbs energy from a photon , it may become excited and move to a higher-energy shell ; conversely , when an excited electron dro...
so should n't 4s/4p have higher energy than 3d ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in order to move between shells , an electron must absorb or release an amount of energy corresponding exactly to the difference in energy between the shells . for instance , if an electron absorbs energy from a photon , it may become excited and move to a higher-energy shell ; conversely , when an excited electron dro...
so is the 3d shell higher in energy than the 4s shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
i was wondering - how do the rows/periods of the periodic table relate to orbit being filled ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
we can break each electron shell down into one or more subshells , which are simply sets of one or more orbitals . subshells are designated by the letters $ s $ , $ p $ , $ d $ , and $ f $ , and each letter indicates a different shape . for instance , $ s $ subshells have a single , spherical orbital , while $ p $ subs...
sal says p sub z is up and down , while p sub y is forward in backwards , but this article says that p sub z is forward and backward while p sub y is up and down , which would make a little more sense because it fits in with graphing in math , but which one is correct ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
what is a quick way to learn the materials on the periodic table ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
most of organic chemistry—the chemistry of carbon-containing compounds , which are central to biology—involves interactions between electrons in $ s $ and $ p $ subshells , so these are the most important subshell types to be familiar with . however , atoms with many electrons may place some of their electrons in $ d $...
can a hydrogen atom have no electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
hydrogen and helium are the only two elements that have electrons exclusively in the $ 1s $ orbital in their neutral , non-charged , state . the second electron shell , 2n , contains another spherical $ s $ orbital plus three dumbbell-shaped $ p $ orbitals , each of which can hold two electrons . after the $ 1s $ orbit...
does anyone know why p shell only have 3 orbitals but 6 electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
specifically , electrons don ’ t really circle the nucleus , but rather spend most of their time in sometimes-complex-shaped regions of space around the nucleus , known as electron orbitals . we can ’ t actually know where an electron is at any given moment in time , but we can mathematically determine the volume of sp...
why ca n't we know exactly where an electron is at any given time ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
is there any way to mathematically find out how a shell / sub shell will fill up ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
why is the table in a specific shape ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
atoms , like other things governed by the laws of physics , tend to take on the lowest-energy , most stable configuration they can . thus , the electron shells of an atom are populated from the inside out , with electrons filling up the low-energy shells closer to the nucleus before they move into the higher-energy she...
how many shells can an atom have ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
if we consider just the first three rows of the table , which include the major elements important to life , each row corresponds to the filling of a different electron shell : helium and hydrogen place their electrons in the 1n shell , while second-row elements like li start filling the 2n shell , and third-row elemen...
could someone give me an example of how an element in th `` b '' column is written ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in addition , the position of an element in the periodic table—its column , or group , and row , or period—provides useful information about how those electrons are arranged . if we consider just the first three rows of the table , which include the major elements important to life , each row corresponds to the filling...
how does filling the d shell work ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , when their outermost electron shell is full . most of the elements important in biology need eight electrons in their outermost shell in order to be sta...
are elements constantly looking to be stable ( have a full outer shell ) ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
on the periodic table , hydrogen and helium are the only two elements in the first row , or period , which reflects that they only have electrons in their first shell . hydrogen and helium are the only two elements that have electrons exclusively in the $ 1s $ orbital in their neutral , non-charged , state . the second...
how the tendencies of metal and non metallic elements of the third peeriod , was shown by the arrows to illustrate the increase direction of the metal and non metal ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
electron configurations and the periodic table elements are placed in order on the periodic table based on their atomic number , how many protons they have . in a neutral atom , the number of electrons will equal the number of protons , so we can easily determine electron number from atomic number . in addition , the p...
how would we come to know number of elements in an period easily ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
why is the table in a specific shape ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the position of each element in the table gives important information about its structure , properties , and behavior in chemical reactions . specifically , an element ’ s position in the periodic table helps you figure out its electron configuration , how the electrons are organized around the nucleus . atoms use thei...
how can we know the electron configuration of an element if we do n't know the element but know something like its frequency ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital . hydrogen has just one electron , so it has a single spot in the $ 1s $ orbital occupied .
if the orbital notation is 4p ( ) ( ) ( ) are there any electrons in the blank orbitals or do you count them as zeros ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
because its 2n shell is filled , it is energetically stable as a single atom and will rarely form chemical bonds with other atoms . the third electron shell , 3n , also contains an $ s $ orbital and three $ p $ orbitals , and the third-row elements of the periodic table place their electrons in these orbitals , much as...
also , is the number of electrons that a shell ( orbital ) can contain different in different elements ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in this article , we ’ ll look in more detail at the periodic table , how atoms organize their electrons , and how this allows us to predict the reactivity of elements . the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . dev...
why are the lanthanides and actinides under the rest of the periodic table ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
these electron configurations make helium and neon very stable . although argon does not technically have a full outer shell , since the 3n shell can hold up to eighteen electrons , it is stable like neon and helium because it has eight electrons in the 3n shell and thus satisfies the octet rule . in contrast , chlorin...
i do n't understand why , electrons in the 3n shell can not fit in d orbital ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
looking at hydrogen , for example , its symbol , $ \text { h , } $ and name appear , as well as its atomic number of one—in the upper left-hand corner—and its relative atomic mass of 1.01 . differences in chemical reactivity between elements are based on the number and spatial distribution of their electrons . if two a...
what does `` spatial distribution of their electrons '' mean ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
similarly , neon has a complete outer 2n shell containing eight electrons . these electron configurations make helium and neon very stable . although argon does not technically have a full outer shell , since the 3n shell can hold up to eighteen electrons , it is stable like neon and helium because it has eight electro...
can two neon atoms come together and make a molecule ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
thus , the electron shells of an atom are populated from the inside out , with electrons filling up the low-energy shells closer to the nucleus before they move into the higher-energy shells further out . the shell closest to the nucleus , 1n , can hold two electrons , while the next shell , 2n , can hold eight , and t...
how would i know how many electrons each shell or orbital around an atom can hold ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
similarly , neon has a complete outer 2n shell containing eight electrons . these electron configurations make helium and neon very stable . although argon does not technically have a full outer shell , since the 3n shell can hold up to eighteen electrons , it is stable like neon and helium because it has eight electro...
in so4 , why does sulphur make 3 extra covalent bonds ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
helium has two electrons , so it can completely fill the $ 1s $ orbital with its two electrons . this is written out as $ 1s^ 2 $ , referring to the two electrons of helium in the $ 1s $ orbital . on the periodic table , hydrogen and helium are the only two elements in the first row , or period , which reflects that th...
i chose a random line with this this is written out as 1s^ 21s 2 1 , s , start superscript , 2 , end superscript , referring to the two electrons why s ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
similarly , neon has a complete outer 2n shell containing eight electrons . these electron configurations make helium and neon very stable . although argon does not technically have a full outer shell , since the 3n shell can hold up to eighteen electrons , it is stable like neon and helium because it has eight electro...
how do you figure out the electron configurations for lead ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
how many electrons can fit in each shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit .
why does nitrogen have greater 1st ionization potential than oxygen ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
atoms , like other things governed by the laws of physics , tend to take on the lowest-energy , most stable configuration they can . thus , the electron shells of an atom are populated from the inside out , with electrons filling up the low-energy shells closer to the nucleus before they move into the higher-energy she...
what shells do the transitional metals in the middle row have ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the bohr model shows the atom as a central nucleus containing protons and neutrons , with the electrons in circular electron shells at specific distances from the nucleus , similar to planets orbiting around the sun . each electron shell has a different energy level , with those shells closest to the nucleus being lowe...
when we say the closest orbital to the nucleus has low energy levels compared to an orbital farther away from the nucleus , what energy are we talking about ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in general , the number of valence electrons is the same within a column and increases from left to right within a row . group 1 elements have just one valence electron and group 18 elements have eight , except for helium , which has only two electrons total . thus , group number is a good predictor of how reactive eac...
if the 1a group tend to throw one electron away and the 7a group tend to pick up one electron , then why ca n't they just become ion ( na+ , cl- ) , why do they need to become molecule ( nacl ) ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital . hydrogen has just one electron , so it has a single spot in the $ 1s $ orbital occupied .
how many orbital shells exist ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
so , how do these mathematically defined orbitals fit in with the electron shells we saw in the bohr model ? we can break each electron shell down into one or more subshells , which are simply sets of one or more orbitals . subshells are designated by the letters $ s $ , $ p $ , $ d $ , and $ f $ , and each letter indi...
can the electrons of one shell `` jump '' to another one close to it , but still keeping the configuration ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
each electron shell has a different energy level , with those shells closest to the nucleus being lower in energy than those farther from the nucleus . by convention , each shell is assigned a number and the symbol n—for example , the electron shell closest to the nucleus is called 1n . in order to move between shells ...
for example swap or jump from the 2p6 ( x axis ) dumpbell to the 2s2 shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
subshells and orbitals the bohr model is useful to explain the reactivity and chemical bonding of many elements , but it actually doesn ’ t give a very accurate description of how electrons are distributed in space around the nucleus . specifically , electrons don ’ t really circle the nucleus , but rather spend most o...
how is even possible for the electrons to move in such strange patterns and dont `` fly '' away from the nucleus ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
are n't all elements supposed to have 8 valence electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
these properties determine an element ’ s physical state at room temperature—gas , solid , or liquid ) —as well as its chemical reactivity , the ability to form chemical bonds with other atoms . in addition to listing the atomic number for each element , the periodic table also displays the element ’ s relative atomic ...
in the description above , why mass of the hydrogen is give as `` relative atomic mass '' ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in general , atoms are most stable , least reactive , when their outermost electron shell is full . most of the elements important in biology need eight electrons in their outermost shell in order to be stable , and this rule of thumb is known as the octet rule . some atoms can be stable with an octet even though their...
how is the octet rule significant ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
as we will see below , the periodic table organizes elements in a way that reflects their number and pattern of electrons , which makes it useful for predicting the reactivity of an element : how likely it is to form bonds , and with which other elements . electron shells and the bohr model an early model of the atom w...
can there be five electron shells in the atomic model , or is it just the old atomic model ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
thus , group number is a good predictor of how reactive each element will be : helium ( $ \text { he } $ ) , neon ( $ \text { ne } $ ) , and argon ( $ \text { ar } $ ) , as group 18 elements , have outer electron shells that are full or satisfy the octet rule . this makes them highly stable as single atoms . because of...
how could people see atoms ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
carbon ( $ \text { c } $ ) , as a group 14 element , has four electrons in its outer shell . carbon typically shares electrons to achieve a complete valence shell , forming bonds with multiple other atoms . thus , the columns of the periodic table reflect the number of electrons found in each element ’ s valence shell ...
what are covalent and ionic bonds ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
considering the quantum mechanical model , what is the difference in energy 's of the valence electrons of calcium and barium ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
as we will see below , the periodic table organizes elements in a way that reflects their number and pattern of electrons , which makes it useful for predicting the reactivity of an element : how likely it is to form bonds , and with which other elements . electron shells and the bohr model an early model of the atom w...
if the bohr model is an inaccurate representation of electron 's movement , why is it so universally accepted ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
devised by russian chemist dmitri mendeleev ( 1834–1907 ) in 1869 , the table places elements into columns—groups—and rows—periods—that share certain properties . these properties determine an element ’ s physical state at room temperature—gas , solid , or liquid ) —as well as its chemical reactivity , the ability to f...
how do the properties helps to determine the physical state of an element ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
by convention , each shell is assigned a number and the symbol n—for example , the electron shell closest to the nucleus is called 1n . in order to move between shells , an electron must absorb or release an amount of energy corresponding exactly to the difference in energy between the shells . for instance , if an ele...
how do elements achieve their goal of gaining full outer energy shells ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit .
does it always have to be 3 lines or can there be more ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
most of organic chemistry—the chemistry of carbon-containing compounds , which are central to biology—involves interactions between electrons in $ s $ and $ p $ subshells , so these are the most important subshell types to be familiar with . however , atoms with many electrons may place some of their electrons in $ d $...
what is an electrons subshell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
this is why third-row elements , such as argon , can be stable with just eight valence electrons : their $ s $ and $ p $ subshells are filled , even though the entire 3n shell is not . while electron shells and orbitals are closely related , orbitals provide a more accurate picture of the electron configuration of an a...
what is the difference between electron orbitals and shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
electron configurations and the periodic table elements are placed in order on the periodic table based on their atomic number , how many protons they have . in a neutral atom , the number of electrons will equal the number of protons , so we can easily determine electron number from atomic number . in addition , the p...
is an atom only considered full if it is occupied by 8 electrons..in many examples the slot 2s2 ( 2 being the max number ) is seen as valence meaning it is not filled ... but it is filled because it can only fit two ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
why does la have 2 valence electrons ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
these patterns do not fill the outermost shell or satisfy the octet rule , making chlorine and sodium reactive , eager to gain or lose electrons to reach a more stable configuration . electron configurations and the periodic table elements are placed in order on the periodic table based on their atomic number , how man...
where on the periodic table does it tell you the number of protons and nutrons in an atom ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
electron shells and the bohr model an early model of the atom was developed in 1913 by the danish scientist niels bohr ( 1885–1962 ) . the bohr model shows the atom as a central nucleus containing protons and neutrons , with the electrons in circular electron shells at specific distances from the nucleus , similar to p...
why does n't the electron fall into the positively charged nucleus ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
so , how do these mathematically defined orbitals fit in with the electron shells we saw in the bohr model ? we can break each electron shell down into one or more subshells , which are simply sets of one or more orbitals . subshells are designated by the letters $ s $ , $ p $ , $ d $ , and $ f $ , and each letter indi...
first , one question , so i can have a basis for the follow-up questions : is the 'p ' orbital one and the same for every shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
subshells $ d $ and $ f $ have more complex shapes and contain five and seven orbitals , respectively . the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital .
does the 3rd electron shell contain a d sub-shell ( 5 orbitals ) or a single d orbital ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
however , atoms with many electrons may place some of their electrons in $ d $ and $ f $ subshells . subshells $ d $ and $ f $ have more complex shapes and contain five and seven orbitals , respectively . the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital ...
the way it reads is that a sub-shell d must contain 5 orbitals , so if it is not a typo , how can the 3rd shell only contain 1 d orbital ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
in general , the number of valence electrons is the same within a column and increases from left to right within a row . group 1 elements have just one valence electron and group 18 elements have eight , except for helium , which has only two electrons total . thus , group number is a good predictor of how reactive eac...
so the only reason why helium is grouped in group 18 elements is cause it fulfills the octet rule of full outer shell ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
atoms , like other things governed by the laws of physics , tend to take on the lowest-energy , most stable configuration they can . thus , the electron shells of an atom are populated from the inside out , with electrons filling up the low-energy shells closer to the nucleus before they move into the higher-energy she...
in the 21st paragraph , how do you know which electrons go in which sub-shells ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
these patterns do not fill the outermost shell or satisfy the octet rule , making chlorine and sodium reactive , eager to gain or lose electrons to reach a more stable configuration . electron configurations and the periodic table elements are placed in order on the periodic table based on their atomic number , how man...
why does n't d-block directly correspond to the row number in the periodic table like s-block and p-block do ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the first electron shell , 1n , corresponds to a single $ 1s $ orbital . the $ 1s $ orbital is the closest orbital to the nucleus , and it fills with electrons first , before any other orbital . hydrogen has just one electron , so it has a single spot in the $ 1s $ orbital occupied .
what kinds of experiments have shown/proven the orbital shapes as we currently understand them ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the number of electrons in the outermost shell of a particular atom determines its reactivity , or tendency to form chemical bonds with other atoms . this outermost shell is known as the valence shell , and the electrons found in it are called valence electrons . in general , atoms are most stable , least reactive , wh...
if we lose all the valence electrons , would it be called a noble ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
subshells and orbitals the bohr model is useful to explain the reactivity and chemical bonding of many elements , but it actually doesn ’ t give a very accurate description of how electrons are distributed in space around the nucleus . specifically , electrons don ’ t really circle the nucleus , but rather spend most o...
why does n't the electron/electrons , simply crash into the nucleus via electromagnetic attraction ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
the periodic table by convention , elements are organized in the periodic table , a structure that captures important patterns in their behavior . devised by russian chemist dmitri mendeleev ( 1834–1907 ) in 1869 , the table places elements into columns—groups—and rows—periods—that share certain properties . these prop...
if we heat helium at what temperature will it lose its noble properties ?
introduction at some point in your chemistry education , you may have been introduced to the song “ the elements , ” in which tom lehrer does a rapid-fire musical rendition of all the elements ' names . like me , you may even have been offered the opportunity to memorize this song for extra credit . if so , it ’ s poss...
most of organic chemistry—the chemistry of carbon-containing compounds , which are central to biology—involves interactions between electrons in $ s $ and $ p $ subshells , so these are the most important subshell types to be familiar with . however , atoms with many electrons may place some of their electrons in $ d $...
how many electrons are there in 5n ?
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
for example , before running : update users set deleted = true where id = 1 ; you could run : select id , deleted from users where id = 1 ; once you decide to run the update , you can use the limit operator to make sure you do n't accidentally update too many rows : update users set deleted = true where id = 1 limit 1 ...
what are the acid principles ?
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
in that case , you should run in a transaction . for example , the following commands create a row denoting that a user earned a badge , and then update the user 's recent activity to describe that : insert into user_badges values ( 1 , `` sql master '' , `` 4pm '' ) ; update user set recent_activity = `` earned sql ma...
if i add user input to my database , what are the best practices to prevent such an attack ?
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to make your sql safer , however . avoiding bad updates/deletes before y...
are these best practices for ms sql or mysql ?
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
it may be that we only want an update to go through if another update goes through as well , so we want to put both of them in the same transaction . in that case , we can wrap the commands in begin transaction and commit : begin transaction ; update people set husband = `` winston '' where user_id = 1 ; update people ...
with the concept of `` begin transaction '' , would it do the operations in order such as for example : begin transaction ; update people set husband = `` winston '' where user_id = 1 ; update people set wife = `` winnefer '' where husband = `` winston '' ; commit ; will user-id = 1 have husband `` winston '' and wife ...
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
as a general rule , there should be only a few users that have full access to the database ( like backend engineers ) , since it can be so dangerous . for example , here 's how we can give full access to a particular user : grant full on table users to super_admin ; and here 's how we can give only select access to a d...
in the paragraph about the command grant , what would grant select on table users to analyzing_user do ?
sql can be a beautiful thing , but it can also be a dangerous thing . if you 're using sql to access a database for an app that 's used by hundreds or thousands or even millions of users , you need to be careful - because you could accidentally damage or erase all that data . there are various techniques you can use to...
in that case , we can wrap the commands in begin transaction and commit : begin transaction ; update people set husband = `` winston '' where user_id = 1 ; update people set wife = `` winnefer '' where user_id = 2 ; commit ; if the database is unable to issue both those update commands for some reason , then it will ro...
are transactions similar to locks and synchronized blocks in other languages ?