What makes phenols more acidic than alcohols?

Phenols are more acidic than alcohols primarily because they can stabilize the negative charge that results from deprotonation through resonance. When a phenol loses a hydrogen ion (H+), it forms a phenoxide ion. The negative charge on this ion can be delocalized across the benzene ring via resonance structures, which spreads the charge over multiple atoms. This stabilization significantly lowers the energy of the anion compared to alcohols, where the negative charge on the alkoxide ion is localized on a single oxygen atom without any significant resonance stabilization.

In contrast, alcohols do not have a system that allows for such resonance stabilization. The negative charge on their corresponding alkoxide ions is held solely by the oxygen atom, making them less stable compared to the phenoxide ions derived from phenols. While phenols do have hydroxyl groups like alcohols, this feature alone does not account for the difference in acidity — it is the accompanying resonance stabilization that enhances the acidity of phenols.