Chapter 18 examines the chemistry of carboxylic acids and their principal derivatives, esters. The chapter covers the preparation and reactions of both classes of compound, and develops the conceptual basis for understanding their relative reactivity.

The chapter opens with carboxylic acids, examining the reactions by which they are prepared and their characteristic reactions with metals, alkalis, carbonates, alcohols and reducing agents. The formation of esters by condensation of a carboxylic acid with an alcohol in the presence of concentrated sulfuric acid is described, and the hydrolysis of esters under both acidic and alkaline conditions is treated. The chapter also covers the preparation of nitriles and hydroxynitriles and the hydrolysis of nitriles to carboxylic acids, providing further examples of the interconversion of functional groups that is central to organic synthesis at this level.