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carbonyls a level chemistry

for this question, please can you explain why the answer is C and not B
(edited 8 months ago)
Original post by taqiyah
for this question, please can you explain why the answer is C and not B


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Original post by JA03
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i have attached it now
Original post by taqiyah
i have attached it now


B would be C5H8O3 if refluxed because it has an aldehyde on one end (-CHO) which would oxidise into a carboxylic acid (-COOH) and a secondary alcohol which would oxidise into a ketone (C=O)

CH3CH(OH)CH(CH3)CHO 2[O] —> CH3COCH(CH3)COOH H2O

So it can’t be B because the molecular formula doesn’t match the one in the question.
(edited 8 months ago)
C has a ketone and a secondary alcohol. Ketones can’t be oxidised any further but secondary alcohols can be oxidised into ketones.

CH3CH(OH)COCH2CH3 + [O] —> CH3COCOCH2CH3 + H2O.

Molecular for this is C5H8O2 which matches the question and we know this is correct because aldehydes are the only carbonyls that can oxidise further.

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