Give reason: phenol is more acidic than ethanol.

Phenol is more acidic than ethanol because the phenoxide ion is resonance-stabilized, while the ethoxide ion is not.

Acidity depends on the stability of the conjugate base. When phenol (C₆H₅OH) loses a proton, it forms the phenoxide ion (C₆H₅O⁻). The negative charge delocalizes over the aromatic ring through resonance. This spreads the charge and stabilizes the ion, so releasing H⁺ is easier.

Ethanol (CH₃CH₂OH), after deprotonation, forms ethoxide (CH₃CH₂O⁻). The charge stays localized on oxygen because there is no aromatic ring to delocalize it. Alkyl groups also push electrons, which destabilizes the base and reduces acidity of the alcohol.

Evidence and comparisons

• pKₐ values: Phenol ≈ 10; Ethanol ≈ 16. Lower pKₐ means stronger acid.
• Reaction test: Phenol reacts with NaOH to form sodium phenoxide. Ethanol is less likely to react with weak bases and needs stronger base like sodium metal.
• Substituents: Electron-withdrawing groups on the ring make phenol even more acidic; electron-donating groups make it less acidic.

So, resonance and ring effects explain the higher acidity of phenol. This concept appears across organic chemistry: more stable conjugate base → stronger acid.