Phenols Contain an Acidic Hydroxyl Croup

Phenols contain a phenolic group, which consists of a hydroxyl group attached to a benzene ring. Because of the presence of the benzene ring, the hydrogen of the hydroxyl group is readily lost in an acid-base reaction, which makes the phenolic group mildly acidic. 

Ethanol can be synthesized ftom the unsaturated hydrocarbon ethene, with phosphoric acid as a catalyst. 

The iK ative charge of the phenoxide ion is able to migrate to select positions on ihe lx n7.ene ring. This mobility helps to accommodate the negative charge, which is why the phenolic group readily donates a hydrogen ion. 

Every phenol contains a phenolic group (highlighted in blue). 

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