Tags: Chemical Compound, Chemical Substance.
Acetylenedicarboxylic acid or butynedioic acid is an organic compound (a dicarboxylic acid) with the formula C4H2O4 or HO2C-C≡C-CO2H. It is a crystalline solid that is soluble in diethyl ether. The removal of two protons yields the acetylenedicarboxylate dianion C4O42− which consists only of carbon and oxygen making it an oxocarbon anion.
