, C₇H₆O₂ (or C₆H₅COOH), is a colorless crystalline solid and the simplest aromatic carboxylic acid. Its salts are used as a food preservative and benzoic acid is an important precursor for the synthesis of many other organic substances. It is a kind of bulk pharmaceutical chemical. There are some basic informations about this crude drug: (1)CAS No.: ; (2)Molecular formula: C₆H₅COOH ; (3)Molar mass: 122.12 g/mol ; (4)Appearance: Colorless crystalline solid; (5)PubChem: 243; (6)ChemSpider: 238; (7)UNII: 8SKN0B0MIM ; (8)EC number: 200-618-2; (9)Solubility in water: Soluble (hot water) 0.34 g/100ml (25 °C); (10)Solubility in THF, ethanol, methanol: THF 3.37 M, ethanol 2.58 M, methanol 2.91 M.

Benzoic acid is produced commercially by partial oxidation of toluene with oxygen. The process is catalyzed by cobalt or manganese s. The process uses cheap raw materials, proceeds in high yield, and is considered environmentally green.

Benzoic acid is used to make a large number of chemicals; important examples of which are:

♦ , C₆H₅C(O)Cl, is obtained by treatment of benzoic with chloride, phosgene or one of the chlorides of phosphorus. C₆H₅C(O)Cl is an important starting material for several benzoic acid derivates like benzyl benzoate, which is used in artificial flavours and insect repellents.
♦ Benzoate plasticizers, such as the glycol-, diethylengylcol-, and triethylenes, are obtained by transesterification of methyl benzoate with the corresponding diol. Alternatively these species arise by treatment of benzoylchloride with the diol. These plasticizers are used similarly to those derived from terephthalic acid ester.
♦ , C₆H₅OH, is obtained by oxidative decarboxylation at 300-400°C. The temperature required can be lowered to 200°C by the addition of catalytic amounts of copper(II) salts. The phenol can be converted to cyclohexanol, which is a starting material for nylon synthesis.

Benzoic acid and its salts are used as a food preservative, represented by the E-numbers E210, E211, E212, and E213. Benzoic acid is a constituent of Whitfield's Ointment which is used for the treatment of fungal skin diseases such as tinea, ringworm, and athlete's foot.