A benzene polycarboxylic acid is a derivative of benzene with two or more carboxylic acid functional groups. These compounds have the chemical formula or .
Benzenedicarboxylic acid, , three isomers: Isophthalic acid (1,2-benzenedicarboxylic acid) Phthalic acid (1,3-benzenedicarboxylic acid) Terephthalic acid (1,4-benzenedicarboxylic acid) Benzenetricarboxylic acid, , three isomers: Hemimellitic acid (1,2,3-benzenetricarboxylic acid) Trimellitic acid (1,2,4-benzenetricarboxylic acid) Trimesic acid (1,3,5-benzenetricarboxylic acid) Benzenetetracarboxylic acid, , three isomers: 1,2,3,4-benzenetetracarboxylic acid 1,2,3,5-benzenetetracarboxylic acid Pyromellitic acid (1,2,4,5-benzenetetracarboxylic acid) Benzenepentacarboxylic acid, Mellitic acid (benzenehexacarboxylic acid),