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Multiple Choice

Under acid hydrolysis, which description matches the ester hydrolysis in the scheme?

Acid-catalyzed hydrolysis of an ester turns the ester into a carboxylic acid and an alcohol. In this reaction, water enters the process in the presence of an acid, protonating the carbonyl to make it more susceptible to nucleophilic attack by water, followed by proton transfers and collapse to the two products. Therefore, describing the reaction as ester + H2O with H+ (acid hydrolysis) captures the actual reactants, the reagent, and the products: a carboxylic acid and an alcohol. The other options don’t fit: forming an alcohol and a carboxylic acid would be the products, not the description of the hydrolysis itself; an acid chloride is a different starting material; base would imply base-catalyzed hydrolysis (saponification) giving a carboxylate salt rather than a free carboxylic acid under acidic conditions.

Acid-catalyzed hydrolysis of an ester turns the ester into a carboxylic acid and an alcohol. In this reaction, water enters the process in the presence of an acid, protonating the carbonyl to make it more susceptible to nucleophilic attack by water, followed by proton transfers and collapse to the two products. Therefore, describing the reaction as ester + H2O with H+ (acid hydrolysis) captures the actual reactants, the reagent, and the products: a carboxylic acid and an alcohol. The other options don’t fit: forming an alcohol and a carboxylic acid would be the products, not the description of the hydrolysis itself; an acid chloride is a different starting material; base would imply base-catalyzed hydrolysis (saponification) giving a carboxylate salt rather than a free carboxylic acid under acidic conditions.