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Assertion : Alcohols and water are wea...

Assertion : Alcohols and water are weaker acids than phenols.
Reason : The delocalisation of negative charge makes the phenoxide ion more stable and favour the ionisation of phenol.

A

If both (A) and (R) are correct and (R) is the correct explanation of (A).

B

If both (A) and (R) are correct, but (R) is not the correct explanation of (A)

C

If (A) is correct, but (R) is incorrect

D

If both (A) and (R) are incorrect.

Text Solution

Verified by Experts

The correct Answer is:
A
The reaction of phenol with aqueous NaOH indicates that phenols are stronger acids than alcohols and water. Due to the higher electronegativity of `sp^2` hybridised carbon ofphenol to which OH is attached, electron density decreases on oxygen. This increases the polarity of OH bond and results in an increase. in ionisation of phenols than that of alcohols. In alkoxide ion, the negative.charge is localised on oxygen while in phenoxide ion, the charge is delocalised. The delocalisation of negative charge makes phenox - ide ion more stable and favours the ionisation of phenol.
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