Benzoic acid and benzoic acid, molecular formula for C6H5COOH,, is a hydrogen of benzene ring replaced by carboxyl (-cooh) group – formation of the compound. Under normal temperature with the smell of benzene and formaldehyde scaly or needle crystal. Its vapor strong excitant, easy cause cough after inhaling. Slightly soluble in water, soluble in ethanol, ether and other organic solvents.