Which of the following is not disproportionation reaction?

Which of the following is not disproportionation reaction?
  1. $2 \mathrm{PhCHO} \stackrel{\mathrm{Al}(\mathrm{OEt})_{3}}{\longrightarrow} \mathrm{PhCOOCH}_{2} \mathrm{Ph}$
  3. $\mathrm{NaH}+\mathrm{H}_{2} \mathrm{O} \longrightarrow \mathrm{NaOH}+\mathrm{H}_{2}$
  4. All of the above.

Solution

(a) and (b) are disproportionation reactions.
(c) is an oxidation reaction.
$2 \mathrm{H}^{-} \longrightarrow \mathrm{H}_{2}+2 \mathrm{e}^{-}$

Asked in: JEE-TOPICTESTS-CHEMISTRY

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