Assertion (A): pK_a of phenol is 4.19 and tha | vedclass

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(D) $pK_a = -\log K_a$. As $K_a$ increases,$pK_a$ decreases.Benzoic acid $(pK_a \approx 4.2)$ is a stronger acid than phenol $(pK_a \approx 10)$,so th

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$A$ is false,but $R$ is true.

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(D) $pK_a = -\log K_a$. As $K_a$ increases,$pK_a$ decreases.Benzoic acid $(pK_a \approx 4.2)$ is a stronger acid than phenol $(pK_a \approx 10)$,so the $pK_a$ of benzoic acid is smaller than that of phenol.Therefore,Assertion $(A)$ is false.The phenoxide ion is stabilized by non-equivalent resonance structures,while the benzoate ion is stabilized by two equivalent resonance structures,which makes the benzoate ion more stable and benzoic acid a stronger acid.Thus,Reason $(R)$ is true.

Assertion $(A)$: $pK_a$ of phenol is $4.19$ and that of benzoic acid is $10$.
Reason $(R)$: Phenoxide ion is stabilised by non-equivalent resonance structures,whereas benzoate ion is stabilised by two equivalent resonance structures.
The correct option among the following is:

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Assertion $(A)$: $pK_a$ of phenol is $4.19$ and that of benzoic acid is $10$.Reason $(R)$: Phenoxide ion is stabilised by non-equivalent resonance structures,whereas benzoate ion is stabilised by two equivalent resonance structures.The correct option among the following is: