Although phenoxide ion has more number of resonating structures than carboxylate ion, carboxylic acid is a stronger acid than phenol. Why?

Explanation

The resonating structures to phenoxide are given as below.


In the resonating structure of phenoxide, a negative charge is present on C atom (Which is less electronegative) while in benzoate ion, a negative charge is present on the more electronegative atoms. Hence, in the ionic structure, if negative charge is present on more electronegative atoms, it is more stable in comparison to the ion which is having negative charge on less electronegative atoms. Thus, due to the higher stability of benzoate ion, it is able to provide more `H^(+)`, and as a result it is more acidic.
`C_(6)H_(5)OH hArr underset(Less stable)C_(6)H_(5)O^(-)+H^(o+)`
`C_(6)H_(5)COOH hArr underset(More stable)C_(6)H_(5)COO^(-) +H^(o+)`
So, the order of acidic strength is `C_(6)H_(5)COOH gt C_(6)H_(5)OH`.