Organic Chemistry MCAT Practice Exam 2026 - Free MCAT Practice Questions and Study Guide

When an alcohol reacts with a carboxylic acid, the compound formed is an ester. This reaction is known as esterification. During this process, the hydroxyl group (-OH) from the carboxylic acid is removed, and a hydrogen atom from the alcohol is also removed, resulting in the formation of water as a byproduct. The remaining parts of the alcohol and carboxylic acid then combine to form the ester functional group.

Esters are characterized by the presence of the functional group –COOR, where R represents an alkyl or aryl group. This reaction is not only important in organic chemistry, but it also occurs naturally, as many esters are responsible for the aromas and flavors of fruits and flowers.

Understanding the chemistry behind the formation of esters is essential for grasping broader concepts in organic synthesis and functional group transformations.