Why are aliphatic carboxylic acids stronger than phenols?

Explanation

The aliphatic carboxylic acids are stronger acids than phenols. The difference in the relative acidic strengths can be understood if we compare the resonance hybrids of carboxylate ion and phenoxide ion.

The electron charge in the carboxylate ion is more dispersed in comparison to the phenate ion since there are two electronegative oxygen atoms in carboxylate ion as compared to only one oxygen atom in phenate ion. In other words, the carboxylate ion is relatively more stable as compared to phenate ion. Thus, the release of `H^(+)` ion from carboxylic acid is comparatively easier or it behaves as a stronger acid than phenol.