CBSE 2026 · Region 1 · Set 1 · Q26 · 3 marks
Give reasons for the following :(a)Carboxylic acids have higher boiling point than alcohols of comparable molecular masses.(b)Alpha ( $\displaystyle \alpha$ ) hydrogens of aldehydes and ketones are acidic in nature.(c)Nucleophilic addition of ammonia and its derivatives does not occur with carbonyl group in strongly acidic medium.
Give reasons for the following :
(a)
Carboxylic acids have higher boiling point than alcohols of comparable molecular masses.
(b)
Alpha ( $\displaystyle \alpha$ ) hydrogens of aldehydes and ketones are acidic in nature.
(c)
Nucleophilic addition of ammonia and its derivatives does not occur with carbonyl group in strongly acidic medium.
Marking-scheme solution
(a)
Due to extensive association of carboxylic acid molecules through
intermolecular hydrogen bond./ Dimer formation takes place
(b)
Due to the strong electron withdrawing effect of the carbonyl group /
resonance stabilisation of their conjugate base.
(c)
Protonation of nucleophile takes place in strongly acidic medium.
Aldehydes, Ketones and Carboxylic AcidsPhysical Properties of Aldehydes, Ketones and Carboxylic AcidsUnderstandshort_answermedium
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