Which of the following organic functional groups contains a carbonyl group bonded directly to a hydroxyl group?

💡 Solution & Explanation

Carboxylic acids contain the carboxyl functional group, which consists of a carbonyl group attached directly to a hydroxyl group, conferring acidic properties due to resonance stabilization of the resulting carboxylate anion. Aldehydes feature a carbonyl group bonded to at least one hydrogen atom, ketones have carbonyl groups bonded to two carbon atoms, and ethers contain oxygen atoms linked between two alkyl or aryl groups. Organic acids like acetic acid and formic acid are classic examples of carboxylic acids.