Phenols are more acidic than alcohols due to
a) In phenols, –OH is attached to sp² hybri-dised carbon but in alcohols, –OH is attached to sp³ hybridised carbon
b) Phenoxide ion is more stable than alkoxide due to resonance
c) Phenoxide ion is more stable than phenol

Reasoning:

Phenols are more acidic than alcohols due to the stabilisation of the phenoxide ion by resonance. When phenol loses a proton (H⁺), it forms a phenoxide ion, where the negative charge on the oxygen is delocalised into the aromatic ring. This resonance effect makes the phenoxide ion more stable compared to the alkoxide ion formed by alcohols.

In alcohols, the –OH group is attached to a sp³ hybridised carbon. When alcohol loses a proton, it forms an alkoxide ion. However, the alkyl group attached to the sp³ carbon has a +I (inductive) effect, which pushes electron density towards the oxygen, making the alkoxide ion unstable. This instability makes alcohols less acidic than phenols.

Key Concepts:

• Phenols are more acidic because the phenoxide ion is stabilised by resonance.
• Alcohols are less acidic due to the destabilising +I effect of the alkyl group in the alkoxide ion.
• The acidity of phenols is governed by the stability of the phenoxide ion, which is stabilised by resonance and delocalisation of the negative charge.
• Therefore, phenols have a stronger tendency to donate a proton, making them more acidic than alcohols.

The key reason why phenols are more acidic than alcohols lies in the resonance stabilisation of the phenoxide ion and the destabilising effect of the alkyl group's +I effect on the alkoxide ion in alcohols. This makes phenols more prone to deprotonation, resulting in a higher acidity.