Question

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

Answer 1

In carboxylate ion -ve charge is delocalised over two oxygen atoms whereas in phenoxide ion the -ve charge is delocalised over one oxygen atom. Therefore carboxylate ion is more stable than phenoxide ion and that is why carboxylic acids are more acidic than phenols.