What does Fehling's solution test detect?
AAcid
BAliphatic aldehydes (gives red Cu₂O precipitate)
CAll ketones
DPhenols
Answer & Solution
Correct answer: B. Aliphatic aldehydes (gives red Cu₂O precipitate)
Fehling's reagent (Cu²⁺ in alkaline tartrate): aliphatic aldehydes reduce Cu²⁺ → red Cu₂O. Aromatic aldehydes (e.g., PhCHO) and ketones give NEGATIVE Fehling test. Tollens distinguishes aliphatic vs aromatic better.
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