C7H5O2

C7H5O2 is most commonly encountered as the benzoate ion, the conjugate base of benzoic acid (C7H6O2). In its neutral context, the formula represents the monoanionic species C7H5O2− that forms salts with various cations, such as sodium benzoate (C7H5O2Na) and potassium benzoate (C7H5O2K). The benzoate anion is a planar, resonance-stabilized carboxylate, with the negative charge delocalized over the two oxygens.

Benzoates play a major role in chemistry and industry as preservatives and intermediates. They are widely used as food additives to inhibit microbial growth, with sodium benzoate and potassium benzoate among the most common examples. In addition to food applications, benzoate salts are used in cosmetics, pharmaceuticals, and as intermediates in the synthesis of esters and other organic compounds.

Preparation typically involves the neutralization of benzoic acid with a base, producing the corresponding salt: C6H5COOH + NaOH → C6H5COONa + H2O. Benzoates can also be prepared by neutralizing benzoic acid with other alkali or alkaline earth bases.

Safety and regulation: benzoates are generally recognized as safe when used within approved limits in foods and consumer products. As with many chemical additives, high concentrations may irritate the skin, eyes, or respire mucosa, and regulatory agencies set specific usage limits to ensure consumer safety.

See also: benzoic acid, benzoate esters.