CUET · CHEMISTRY · PYQ PAPER 2023
Answer the question on basis of passage given below :
A ketone \([ A ]\) which undergoes haloform reaction gives compound \([ B ]\) on reduction. Compound
\([B]\) on heating with sulphuric acid gives compound \([C]\) which forms monozonide \([D]\). The compound \([ D ]\) on hydrolysis in the presence of zinc dust gives compound \([ E ]\).
Compound \([ E ]\) on oxidation gives \(C _2 H _4 O _2\) [F]
Compound [E] in presence of dil NaOH gives :
- A But-2-enal
- B Methanol
- C 2-Methyl but-2-enal
- D Pent-2-enal
Answer & Solution
Correct Answer
(A) But-2-enal
Step-by-step Solution
Detailed explanation
\([E]\) is acetaldehyde (\(CH_3CHO\)) because its oxidation product \([F]\) is acetic acid (\(C_2H_4O_2\)). Acetaldehyde in the presence of dil NaOH undergoes aldol condensation followed by dehydration:…
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