alleryFehling's test positive for:
AKetone
BBoth
CAromatic aldehyde
DALIPHATIC aldehyde (gives red Cu₂O precipitate)
Answer & Solution
Correct answer: D. ALIPHATIC aldehyde (gives red Cu₂O precipitate)
**Fehling's reagent:** Cu²⁺ in alkaline tartrate.
Aliphatic aldehydes reduce Cu²⁺ to red Cu₂O.
Aromatic aldehydes (like benzaldehyde) do NOT give Fehling's test (more stable due to resonance).
**So both Tollens' AND Fehling's together distinguish aliphatic vs aromatic aldehydes.**
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