What reddish precipitate is formed when an aliphatic aldehyde is heated with Fehling's solution?
Answer and explanation
Correct answer: B. Copper(I) oxide
Fehling's solution contains Cu2+ complexed with tartrate in alkaline solution. Aliphatic aldehydes reduce blue Cu2+ to insoluble red-brown copper(I) oxide (Cu2O), while being oxidized to carboxylic acid salts.
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