Chapter Nature and composition of organic acids
An organic acid is an organic compound with acidic properties and containing carbon, as do all organic compounds. The most common organic acids are the carboxylic acids whose acidity is associated with their carboxyl group –COOH. These are generally weak acids, whereas sulfonic acids, containing the group OSO3H, are relatively stronger acids. The acidity of an acid is determined by the relative stability of the conjugate base of the acid, although other groups can also confer acidity. This acidity is, however, usually weak and is the result of the –OH, –SH, enol group, and the phenol group (Figure 2.1) (Theron and Lues, 2007).