CBSE 2022 · Region 4 · Set 2 · Q3 · 2 marks
Give reasons for the following statements : (Any two)(i)Benzaldehyde is less reactive than propanal in nucleophilic addition reactions.(ii)Carboxylic acids do not give reactions of carbonyl group.(iii)$\displaystyle 4$-nitrobenzoic acid is a stronger acid than benzoic acid.
Give reasons for the following statements : (Any two)
(i)
Benzaldehyde is less reactive than propanal in nucleophilic addition reactions.
(ii)
Carboxylic acids do not give reactions of carbonyl group.
(iii)
$\displaystyle 4$-nitrobenzoic acid is a stronger acid than benzoic acid.
Marking-scheme solution
(i) Carbon atom of carbonyl group of benzaldehyde is less electrophilic and polarity is reduced due to resonance.
(ii) Because of resonance by -OH of COOH which reduces the electrophilicity of carboxyl carbon / Because of resonance in COOH group due to which carbon loses its carbonyl nature.
(iii) Due to -I effect /electron withdrawing nature of \(\displaystyle \mathrm{NO}_{2}\) group.
Aldehydes, Ketones and Carboxylic AcidsChemical Reactions of Aldehydes, Ketones and Carboxylic AcidsUnderstandvery_short_answermedium
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