English name cis-Butenedioic anhydride; Maleic anhydride Don't name maleic anhydride Formula C4H2O3; CHCOOCOCH appearance and properties colorless needle crystal Molecular weight 98.06 steam pressure kPa / 20 ℃ to 0.02 ℃ / flash point: 110 open cup Melting point 52.8 ℃ 202 ℃ boiling point: solubility in water, acetone, benzene, chloroform and most organic solvents Dense degrees relative density (water = 1) 1.48; The relative density (air = 1) 3.38 stability stable Risk marker 20 (corrosive) main use manufacture polymer, copolymer, also used in synthetic resin, coating, pesticide, pharmaceutical, food, and the additives lubricating oil etc