Which term describes the reaction of a carboxylic acid with an alcohol to form an ester?

• A. Esterification
• B. Hydrolysis
• C. Saponification
• D. Condensation

Answer: (A)

Estérification describes the formation of an ester from a carboxylic acid and an alcohol, typically via an acid-catalyzed process (often called Fischer esterification) where a molecule of water is removed as the ester forms. This is a condensation-type reaction, since two smaller molecules join and a water molecule is eliminated, but the specific operation of turning a carboxyl group and an alcohol into an ester is best named esterification. The other terms refer to different processes: hydrolysis is the reverse reaction that breaks an ester back into acid and alcohol; saponification is base-catalyzed hydrolysis producing a carboxylate salt and an alcohol; condensation is a broad category of reactions that involve bond formation with loss of a small molecule, not the precise name for this transformation.