H NMR (1 Viewer)

=)(=

Active Member
Joined
Jul 14, 2021
Messages
647
Gender
Male
HSC
2023
1692613061105.png
Im not sure why the answer is A isn't there a hydrogen bonded to a Nitrogen so by n=1 rule shouldn't there be 2 splits?
 

wizzkids

Well-Known Member
Joined
Jul 13, 2016
Messages
332
Gender
Undisclosed
HSC
1998
The H 's bonded to Ns or OH groups do not cause splitting I believe
That is correct. This is a very difficult question to give to high school Chemistry students. It is bad enough that we have to learn about spin-spin coupling to reveal the fine scale structure in proton-NMR spectra. But then to ask students to remember the exceptions to the rule is really cruel, in my opinion. The absence of spin-spin coupling is particularly relevant to primary alcohols; the hydrogen in the hydroxyl OH group does not count as a neighbour for predicting peak-splitting. The spin-spin coupling between adjacent hydrogens normally does not cross over another functional group.
 
Last edited:

=)(=

Active Member
Joined
Jul 14, 2021
Messages
647
Gender
Male
HSC
2023
1692881507863.png
wait also for this which is 13C NMR is it for the carbon bonded to a carbonyl group?
 

synthesisFR

afterhscivemostlybeentrollingdonttakeitsrsly
Joined
Oct 28, 2022
Messages
3,312
Location
Getting deported
Gender
Female
HSC
2028
and how much do u study like damn ur always doing past papers. ive barely started ...
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top