Organic Chemistry MCAT Practice Exam 2025 – The All-in-One Guide to Master Your Test Preparation!

When a carboxylic acid reacts with a primary amine, the primary amine acts as a nucleophile and attacks the electrophilic carbonyl carbon of the carboxylic acid. This reaction results in the formation of an amide, which is characterized by the presence of a carbonyl group (C=O) bonded to a nitrogen atom that is part of the amine.

The process involves the elimination of water (dehydration): the hydroxyl group from the carboxylic acid and a hydrogen from the nitrogen of the amine combine to form water, resulting in the formation of a covalent bond between the carbonyl carbon and the nitrogen atom. This reaction is termed amidation.

In contrast, the other choices do not represent the product of this particular reaction:

- An ester is produced when a carboxylic acid reacts with an alcohol, not an amine.

- An amine itself is a starting reactant, not a product, in this context.

- An ammonium salt may be formed if a carboxylic acid is protonated, but this does not accurately describe the end product when an amine reacts with a carboxylic acid under typical conditions.

Therefore, the correct identification of