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here is a simulation created by khan academy user justin helps that once again tries to give us an understanding of why we divide by n minus 1 to get an unbiased estimate of population variance when we 're trying to calculate the sample variance . so what he does here , the simulation , it has a population that has a u...
sample mean here only a little bit more than the true mean . in the vertical axis , using this denominator , dividing by n , we calculate two different variances . one variance , we use the sample mean .
how did we discover that using n-1 was a better estimation than using dividing by n ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
but they do n't look quite the same . are they mirror images ? well , no .
when we are talking about 'mirror images behind the molecule ' , how do the groups change place ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
you might say , wait , this hydrogen is on the right , this one 's on the left . it does n't matter . this is actually saying that the hydrogen 's pointing out front , the fluorine is pointing out back , hydrogen up front , fluorine back , chlorine out front , hydrogen back , chlorine out front , hydrogen back .
i do n't understand the last example why is it no longer superimposible if you change the `` br '' to a `` f '' and do you have to use the same rotation axis ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
then all of a sudden , you do not have this symmetry . these are mirror images , but they would not be superimposable . so if that was a fluorine , these would actually be enantiomers .
if we had not known it was already an enantiomer , how would we know where to place the mirror ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it is superimposable on its mirror image . so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds .
would n't any even number of chiral carbons = achiral molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules .
do tautomerism only consist of keto-enol conversion ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image . it is superimposable on its mirror image . it is superimposable on its mirror image .
what 's the difference between flipping over and reflecting over a mirror image ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
what is the difference between meso compounds and identical compounds ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is a class of stereoisomers , and we 've brought up this word before . we call this enantiomers . so if each of these are an enantiomers , i 'll say they are enantiomers of each other .
i do n't understand how second example is enantiomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are the same molecules . so it is the same molecule . so this is interesting , and we saw this when we first learned about chirality .
why the second molecule is not a diastereomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
but if you think about it , they are mirror images of each other , and they each have two chiral centers or two chiral carbons . but if you think about it , all you have to do is flip this guy over and you will get this molecule . these are the same molecules . so it is the same molecule .
in the second example at time 7 , how come the fluorine and hydrogen flip and switch which way they are coming out of the paper , but when you flip the cyclohexane the bromines do not switch which way they are coming out of the plane ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
so are meso compounds stereoisomers or not ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
this is a meso compound . it has chiral centers . it has chiral carbons , i guess you could say it . but it is not a chiral compound . and the way to spot these fairly straightforward is that you have chiral centers , but there is a line of symmetry here .
there is said that the molecules are not chiral compounds , but why are those 2 compounds not chiral compounds ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
i guess the best way to visualize it , imagine putting a mirror behind this molecule . if you put a mirror behind this molecule , what would its reflection look like ? so if you put a mirror behind it , in the image of the mirror , this hydrogen would now , since the mirror 's behind this whole molecule , this hydrogen...
why you put the mirror behind in third example ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
how can we name a cyclical compound in r , s method ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so carbon to a fluorine , carbon to a fluorine , carbon to a bromine , carbon to a bromine , carbon to hydrogen in both of then carbon to the methyl group in both . but they do n't look quite the same . are they mirror images ? well , no .
do n't wedges become dashes and vice versa when you simply flip over the mirror ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
you might say , wait , this hydrogen is on the right , this one 's on the left . it does n't matter . this is actually saying that the hydrogen 's pointing out front , the fluorine is pointing out back , hydrogen up front , fluorine back , chlorine out front , hydrogen back , chlorine out front , hydrogen back .
the example shown in is the same molecule is n't it ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are the same molecules . so it is the same molecule . so this is interesting , and we saw this when we first learned about chirality .
what kind of molecule `` flipping '' is legall for molecule to stay the same ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
is the second example that sal gave a meso compound ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
so , in the end , you can define a molecule as chiral only compared with another molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
same thing over there . you have a hydrogen , bromine , hydrogen and a bromine , hydrogen , chlorine , hydrogen , chlorine , hydrogen , chlorine , hydrogen , chlorine . so it 's made up of the same things .
should n't the bromine be behind the plane and the hydrogen above the plane ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
what is the difference between a diastereomer and a chiral molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
for the last compound that is labeled as the same molecule and a meso compound , as it is flipped , does n't the stereochemistry of the substituents switch ( from pointing away from you to pointing towards you , etc ) ... so they are in fact enantiomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so when you have a stereoisomer that is not a mirror , when you have two stereoisomers that are n't mirror images of each other , we call them diastereomers . i always have trouble saying that . let me write it .
is saying a molecule is meso the same as saying the molecule is optically inactive ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here .
is an enantiomer also sometimes referred to as an optical isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are diastereomers , which is essentially saying it 's a stereoisomer that is not an enantiomer . that 's all it means : a stereoisomer , not an enantiomer . a stereoisomer 's either going to be an enantiomer or a diastereomer . now , let 's do this last one .
so , to be clear , a mesocompound is a stereoisomer that is an enantiomer and has a plane of symmetry ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it is the same thing as its mirror image . it is superimposable on its mirror image . it is superimposable on its mirror image .
when we say superimposable on mirror image , that means you take the mirror image and directly put it on the original molecule with no rotation or anything ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
well , if i take this fluorine and i rotate it to where the hydrogen is , and i take the hydrogen and rotate it to where -- that 's all going to happen at once -- to where the bromine is , and i take the bromine and rotate it to where the fluorine is , i get that . so i can flip it and then i can rotate it around this ...
or does the rule go that you must flip the molecule in order to rotate ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
are they mirror images ? well , no . this guy 's mirror image would have the fluorine popping out here , the hydrogen going back here , and then would have the bromine pointing out here .
is the molecule in a stereoisomer as well ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
how exactly does having a fluorine instead of a bromine change the last compound from a meso compound to an enantiomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
hey , what kind of isomers are glucose and fructose ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so if that was a fluorine , these would actually be enantiomers . and this would not be only one meso compound , it would be two different enantiomers , and one of them would have an r direction and one of them would have an s direction if we go with the naming conventions that we learned .
does geometric refer to e/z and optic refering to r/s ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
i still see two chiral carbon atoms with opposite chiralities in each of the two enantiomers , so should n't the two cancel out and leave an achiral molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
what would be the difference between meso compound and a chiral molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
then all of a sudden , you do not have this symmetry . these are mirror images , but they would not be superimposable . so if that was a fluorine , these would actually be enantiomers . and this would not be only one meso compound , it would be two different enantiomers , and one of them would have an r direction and o...
we are talking about stereoisomers , just wondering if we had to name this compound ( i think its 2-chloro-3-fluro-pentance ) with the r s configurations how would we write it ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
is the second compound pair meso compounds ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are diastereomers , which is essentially saying it 's a stereoisomer that is not an enantiomer . that 's all it means : a stereoisomer , not an enantiomer . a stereoisomer 's either going to be an enantiomer or a diastereomer . now , let 's do this last one .
is the second example an enantiomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
do meso compounds require the molecule to be symmetrical in some way ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
so are meso compounds always the same molecule just with two or more chiral centers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here .
what 's the difference between a stereoisomer and a constitutional isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is a class of stereoisomers , and we 've brought up this word before . we call this enantiomers . so if each of these are an enantiomers , i 'll say they are enantiomers of each other .
the example starting at 1.30 , are these not enantiomers as opposed to the same molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are the same molecules . so it is the same molecule . so this is interesting , and we saw this when we first learned about chirality .
in the last example , how many enantiomeric forms of the molecule there are ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so if i did that , what would it look like ? i would have the carbon , this carbon here . i would have the methyl group on that side now .
or is the third example the same molecule if you rotate the bond between the f and h on the carbon atom and the cl and h on the 2nd carbon atom ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
which type of isomers are cis - trans in ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so it 's made up of the same things . they 're connected in the same way , so they 're definitely stereoisomers . well , we have to make sure they 're not -- well , let 's make sure they 're not the same molecule first .
is there any video explaining the types of stereoisomers - optical , geometrical & conformational isomerism ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and the way to spot these fairly straightforward is that you have chiral centers , but there is a line of symmetry here . there 's a line of symmetry right here . these two sides of the compound are mirror images of each other .
can an enantiomer or diastereomer have a line of symmetry ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
so in other words can an enantiomer have a line of symmetry or is that what separates an enantiomer from a meso compound ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is a class of stereoisomers , and we 've brought up this word before . we call this enantiomers . so if each of these are an enantiomers , i 'll say they are enantiomers of each other .
would the enantiomers presented in this video be configuration enantiomers or conformational enantiomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and it would n't be completely off , but we look a little bit closer , you see that this guy on the left has one , two , three , four carbons , and so does this guy on the right . it has one , two , three , four carbons . this guy on the left has two , four , six , seven , eight hydrogens .
does the rotation of three bonds along the an axis around the chiral centre happen in one step , or do they have to be rotated each separately ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image . it is superimposable on its mirror image . it is superimposable on its mirror image . so even though it has chiral carbons in it , it is not a chiral molecule .
how does the last molecule become enantiomer of its mirror image when we replace br by f ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
why is it important to recognize meso compounds if really they are just the same molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
how come the last example is classified as a meso compound , but the second example , which is also said to be the same molecule , is not ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
do stereoisomers , enantiomers , diastereomers , constitutional isomers and meso compounds imply a relationship between 2 molecules ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it has chiral carbons , i guess you could say it . but it is not a chiral compound . and the way to spot these fairly straightforward is that you have chiral centers , but there is a line of symmetry here .
how to calculate the possible number of diastereomers for a chiral compound ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
how to calculate the number of stereomers in cyclic and acyclic chiral compounds ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
does the molecules have to be chiral to be stereoisomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
why is example # 2 the same compound and example # 3 an enantiomer when they both have different bonds to the atoms ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
you have the carbons on both of them . this carbon looks like a chiral center . it 's bonded to one , two , three different groups .
to determine whether two structures are diasteriomers or the same in a compound with 2 or more stereo-center should i rotate one of those chiral carbon or deal as it is ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
but if you think about it , all you have to do is flip this guy over and you will get this molecule . these are the same molecules . so it is the same molecule .
could anyone explain how the last example depicts the 'same ' molecules ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is a class of stereoisomers , and we 've brought up this word before . we call this enantiomers . so if each of these are an enantiomers , i 'll say they are enantiomers of each other .
should n't these two 1-bromo-1-fluoroethanes be enantiomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are the same molecules . so it is the same molecule . so this is interesting , and we saw this when we first learned about chirality .
why is the 3rd molecule ( introduced 0 ) an enantiomer and not a diastereoisomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it 's bonded to a hydrogen and a chlorine , so it 's made up of the same constituents and they 're bonded in the same way . so these look like -- but the bonding is a little bit different . over here on this one on the left , the hydrogen goes in the back , and over here , the hydrogen 's in the front .
how do i know the spatial position for every atom in a specific bonding ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
i guess the best way to visualize it , imagine putting a mirror behind this molecule . if you put a mirror behind this molecule , what would its reflection look like ? so if you put a mirror behind it , in the image of the mirror , this hydrogen would now , since the mirror 's behind this whole molecule , this hydrogen...
does 'not superimposable ' just mean that , if we would put the actual molecule and the mirror image of a molecule on top of each other and the atoms would n't be the same , for example left and right of the molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
so does that mean all achiral molecules are meso compounds ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
stereo-isomers of 2-isopropyl-5-methyl cyclohexanol is 8 how ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
what is the difference between optical isomers and optically active isomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
how to know that a compound shows both geometrical and optical isomerism ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
how to know that a compound will form an enantiomeric pair ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
is it so that geometric isomers always means cis-trans ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
what is the difference between optical isomers and optically active isomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
what does the addition of the letter et means when added after a compound ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
can you clarify exactly on the difference between a stereoisomers and constitutional isomers please ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
for the last molecule , is n't a feature of the same molecule that it has the same r and s values at the same chiral centers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so if i did that , what would it look like ? i would have the carbon , this carbon here . i would have the methyl group on that side now .
why does the top br carbon on each side have opposite r , s values ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
these are the same molecules . so it is the same molecule . so this is interesting , and we saw this when we first learned about chirality .
at 13.10 sal replaces the bromine with the fluorine molecule , from the plane of symmetry i can easily say that they are enantiomeric compound , but i could n't understand how they differ in terms of mirror image with the original molecule , is n't it super imposable too as of the orignal molecule ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here .
9 , would the constitutional isomer also be called a structural isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
i would have the methyl group on that side now . and then since i flipped it over , the bromine was in the plane of the page . it 'll still be in the plane of the page , but since i flipped it over , the hydrogen , which was in the back , will now be in the front .
when you mention 'in the same plane as the page ' in reference to the bromine atom in the second pair of molecules , does that mean the bromine atom faces towards you ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so let me -- a good thing to do would be to just flip to see the fastest way i could potentially get there . let me just flip it like this . so i 'm going to flip out of the page , you can imagine . i 'm going to flip it like this . so i 'm going to take this methyl group and then put it on the right-hand side .
because if you flip the molecule on the left over to the right/flip 180 degrees , would n't the br groups be going away from you and the two hydrogens coming toward you ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we could put a mirror right there , and they definitely look like mirror images . and this is a chiral carbon here . it 's bonded to one carbon group that is different than this carbon group . this carbon group has a bromine . this carbon group does n't . it just has a bunch of hydrogens on it , if you kind of go in th...
for the 1,2-dibromocyclohexane , if we were doing s and r , can the carbon have the br in both of its groups going around ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
are structural isomers the same as constitutional isomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
same thing over there . you have a hydrogen , bromine , hydrogen and a bromine , hydrogen , chlorine , hydrogen , chlorine , hydrogen , chlorine , hydrogen , chlorine . so it 's made up of the same things .
i 'm not really understanding in the third example at around 5 minutes why you ca n't just rotate the chlorine and hydrogen groups to make it the same molecule as you did in the example just previous with rotating those hydrogen , fluorine and bromine groups ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it is the same thing as its mirror image . it is superimposable on its mirror image . it is superimposable on its mirror image .
what is the difference between superimposable and superposable ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
you might say , wait , this hydrogen is on the right , this one 's on the left . it does n't matter . this is actually saying that the hydrogen 's pointing out front , the fluorine is pointing out back , hydrogen up front , fluorine back , chlorine out front , hydrogen back , chlorine out front , hydrogen back .
why are n't the compounds superimposible ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is interesting , and we saw this when we first learned about chirality . even though we have two chiral centers , this is not a chiral molecule . it is the same thing as its mirror image .
what is the difference between a stereocenter and a chiral centre ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and so this mirror image that i just thought about in white is exactly what this molecule is : hydrogen pointing out in front , hydrogen pointing out in front . you might say , wait , this hydrogen is on the right , this one 's on the left . it does n't matter .
i think sal meant to say `` superposable '' instead of `` superimposable , '' right ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here . now let 's look at this next guy over here...
is there any different between between structural and costituitional isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this is a class of stereoisomers , and we 've brought up this word before . we call this enantiomers . so if each of these are an enantiomers , i 'll say they are enantiomers of each other . they 're steroisomers .
so all enantiomers are stereoisomers , but not all stereoisomers are enantiomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so if that was a fluorine , these would actually be enantiomers . and this would not be only one meso compound , it would be two different enantiomers , and one of them would have an r direction and one of them would have an s direction if we go with the naming conventions that we learned .
cant we just invert the plane on which the compounds are observed ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
it is an asymmetric carbon . it is bonded to four different groups : fluorine , bromine , hydrogen , and then a methyl group . and so 's this one .
readjust and you can now impose fluorine over fluorine and bromine over bromine ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
and we can point to one of them because they really are the same compound . this is a meso compound . it has chiral centers .
what 's the point of knowing if a molecule is a meso compound ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here .
what is the difference between a constitutional isomer and a configurational isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules .
do professional chemists have to remember these terminology ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
but they do n't look quite the same . are they mirror images ? well , no .
so just to clarify ... enantiomers are stereoisomers with non-superimposable mirror images diastereomers are stereoisomers that are not mirror images meso compounds are achiral molecules with superimposable mirror images is this correct ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so this part , you could think of it this way . this is the mirror image of this , this is the mirror image of this part , but this is not the mirror image of that part . so when you have a stereoisomer that is not a mirror , when you have two stereoisomers that are n't mirror images of each other , we call them diaste...
i understand the mirror is behind the molecule , but what is sal 's pov when he is drawing the 'mirror image ' ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
you might say , wait , this hydrogen is on the right , this one 's on the left . it does n't matter . this is actually saying that the hydrogen 's pointing out front , the fluorine is pointing out back , hydrogen up front , fluorine back , chlorine out front , hydrogen back , chlorine out front , hydrogen back .
i do n't understand how you could swap the br and h ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
can you tell me about monosubstituted / disubstituted /trisubsituted isomers ( particularly benzene ) please ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
they 're made up of the same thing , so these are going to be isomers . they 're going to be isomers , and they 're a special type of isomers . in this situation , we do n't have the same bonds .
how do i figure out the number of substituted isomers ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
would n't meso compounds just be called identical than ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
we 're made up of the same things , but the bonds , what is connected to what is different . so we call this a constitutional isomer . so we are essentially made up of the same things , but we are actually two different molecule , actually , two very different molecules here .
i do n't understand how to tell if something is a geometric isomer , i understand how to tell if something is cis/trans , but how can you tell if it 's a geometric isomer ?
in this video , we 're going to look at pairs of molecules and see if they relate to each other in any obvious way or maybe less than obvious way . so these first two right here , they actually look like a completely different molecules . so your gut impulse might be to say that these are completely different molecules...
so even though it has chiral carbons in it , it is not a chiral molecule . and we call these meso compounds . and we can point to one of them because they really are the same compound .
at 13.13 , when you switch from bromine to fluorine , how is that now an enantiomer , both compounds are still oriented the same way in space in all chirality centers , i understand how its no longer meso , but how is it enantiomer when u have wedges and dashes in the same spot on both compounds ?