MCQ
When acetaldehyde is heated with Fehling's solution, it gives a red ppt. of
  • A
    $CuSO_4$
  • B
    $CuO$
  • C
    $Cu_2Cl_2$
  • $Cu_2O$

Answer

Correct option: D.
$Cu_2O$
d
Fehlings solution is a tartaric acid complex of cupric ions.

When acetaldehyde is heated with Fehling's solution, it gives a red precipitate

of $Cu _2 O$

$CH _3 CHO +2 Cu ^{2+}+5 OH ^{-} \stackrel{\Delta}{\longrightarrow} CH _3 COO ^{-}+ Cu _2 O \downarrow+3 H _2 O$

Acetaldehyde is oxidized to acetate ion and cupric ions are reduced to cuprous oxide.

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