BITSAT 2014 Paper

The acidic nature of phenol is due to the formation of stable phenoxide ion in solution $\mathrm{C_6H_5OH}$ + $\mathrm{H_2O}$ ⇄ $\underset{\text{Phenoxide ion}}{\mathrm{C_6H_5O^{-}}} + \mathrm{H_3O^{+}}$ The phenoxide ion is stable due to resonance The negative charge is delocalized in the benzene ring which is a stabilizing factor in the phenoxide ion and increase acidity of phenol. whereas no resonance is possible in alkoxide ions ($\mathrm{RO}^{-}$) derived from alcohol. The negative charge is localized on oxygen atom. Thus, alcohols are not acidic.