Assertion : Phenol is a weaker acid than ethanol. Reason : Groups with $+M$ effect and $-I$ effect decrease…

Assertion : Phenol is a weaker acid than ethanol. Reason : Groups with $+M$ effect and $-I$ effect decrease acidity at $m$-position.
  1. both the assertion and reason are true and reason is a correct explanation of the assertion.
  2. both assertion and reason are true but assertion is not a correct explanation of the assertion.
  3. the assertion is true but the reason is false.
  4. both assertion and reason are false.

Solution

Phenol is a stronger acid than the ethanol. This is due to the resonance stabilisaton of the phenolate ion which is produced after deprotonation.
But there is no such stabilisation in the case of ethanol $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH} \rightleftharpoons \mathrm{C}_2 \mathrm{H}_5 \mathrm{O}^{-}+\mathrm{H}^{+}$ The groups with $+M$ and $-I$ effect decrease the acidity at $p$-position, but at $m$-position the acidity is increased due to $-I$-effect.

Asked in: NEET 2020 (Phase 2)

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