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Past paper question unit 4 chem edexcel (nmr question)

Which of the following has two singlet peaks in its nmr spectrum?

A Methanal,
B Methanol,
C Chloromethane,
D Dichloromethane.
ANY HELP WOULD BE MUCH APPRECIATED :wink:
Reply 1
only methanol - all the others only have one peak since their H atoms are in the same environment
Original post by GDN
only methanol - all the others only have one peak since their H atoms are in the same environment


Cheers mate x
Original post by blueangel328
Which of the following has two singlet peaks in its nmr spectrum?

A Methanal,
B Methanol,
C Chloromethane,
D Dichloromethane.
ANY HELP WOULD BE MUCH APPRECIATED :wink:


Original post by GDN
only methanol - all the others only have one peak since their H atoms are in the same environment

Ik this is an old thread but could someone explain why B would be the answer in a bit more detail please XD
Original post by Stormragexox
Ik this is an old thread but could someone explain why B would be the answer in a bit more detail please XD

Methanol (CH3OH) has two non-equivalent proton environments, and so this gives two peaks. These two environments are: CH3-O and OH.
These two peaks will be singlets; a singlet means that the proton environment in question isn't adjacent to (next to) any other protons.

The three protons in the CH3-O group are adjacent to an oxygen atom, and not any other protons, so this will give a singlet.
The one proton in the OH group also isn't adjacent to any other protons, so this will give a singlet too.

In terms of the other answers, they all only have one singlet peak.
(edited 5 years ago)
Original post by Kian Stevens
Methanol (CH3OH) has two non-equivalent proton environments, and so this gives two peaks. These two environments are: CH3-O and OH.
These two peaks will be singlets; a singlet means that the proton environment in question isn't adjacent to (next to) any other protons.

The three protons in the CH3-O group are adjacent to an oxygen atom, and not any other protons, so this will give a singlet.
The one proton in the OH group also isn't adjacent to any other protons, so this will give a singlet too.

In terms of the other answers, they all only have one singlet peak.

Thank you so much I understand that now xD

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