Ochem Achiever Question

[CSU Undergrad]

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On the second exam it asks what peaks would be shown on a p-xylene (benzene with a methyl on each opposite end). To me there should be one singlet for the methyl groups (two on top of each other so only only one singlet would appear) and one doublet from the H's in the ring.

Achievers answer states two singlets for the methyl goups, which I understand but I would identify it as one singlet since their on top of each other. But what about the H's in the ring, achiever says we shouldnt get splitting anyone know why?

 

[mitshi]

On the second exam it asks what peaks would be shown on a p-xylene (benzene with a methyl on each opposite end). To me there should be one singlet for the methyl groups (two on top of each other so only only one singlet would appear) and one doublet from the H's in the ring.

Achievers answer states two singlets for the methyl goups, which I understand but I would identify it as one singlet since their on top of each other. But what about the H's in the ring, achiever says we shouldnt get splitting anyone know why?

Answer is two singlets no doubt; but I'm pretty sure achiever means one singlet for the methyl group, and the other singlet for H's in the ring due to symmetry of structure. You should look deeper into the solution and get a better grasp of what I mean here. Questions of this kind are easily seen on the DAT.

 

[CSU Undergrad]

Answer is two singlets no doubt; but I'm pretty sure achiever means one singlet for the methyl group, and the other singlet for H's in the ring due to symmetry of structure. You should look deeper into the solution and get a better grasp of what I mean here. Questions of this kind are easily seen on the DAT.

I understand that there would be one peak due to the H's in the ring because of symmetry, but shouldnt the peak be a doublet instead of a singlet? wouldnt a singlet mean that there are no adjacent carbons with H's attached to them?

In this case one adjacent carbon has no H's the other adjacent carbon has one H, which to my knowledge means a doublet. Where am I wrong?

 

[CSU Undergrad]

shortly after I made my last post I figured it out, identical H's cant split each other thats why its a singlet. Thanks, I cant be making these mistakes on the dat.