Choose the correct statement(s) for Wolff Kishner Reaction.
(A) The carbonyl group of aldehyde and ketone is reduced to \( CH_2 \) group.
(B) Wolff Kishner Reaction involves potassium hydroxide and ethylene glycol
(C) The reaction is carried out at a low temperature.
(D) Hydrazine is used in this reaction.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A), (B) and (D) only
The Wolff-Kishner reduction converts the carbonyl group of an aldehyde or ketone into a \( \ce{CH2} \) group. It uses hydrazine, then strong heating with KOH in ethylene glycol.
(A) The carbonyl group of aldehyde and ketone is reduced to \(CH_2\) group. — Correct. The C=O group ends up as \( \ce{CH2} \), so the aldehyde or ketone becomes a hydrocarbon.
(B) Wolff Kishner Reaction involves potassium hydroxide and ethylene glycol — Correct. The hydrazone is decomposed by KOH in ethylene glycol.
(C) The reaction is carried out at a low temperature. — Incorrect. The hydrazone is decomposed by heating strongly; ethylene glycol is used because its high boiling point allows the high temperature (about 450-470 K) that the reaction needs.
(D) Hydrazine is used in this reaction. — Correct. Hydrazine, \( \ce{NH2NH2} \), forms the hydrazone in the first stage.
NCERT (2026-27 edition):
Reduction – …
