title: C4H2O4
text: # C4H2O4
  
  The molecular formula $C_4H_2O_4$ (molar mass: 114.06 g/mol, exact mass: 113.9953 u) may refer to:
  
  * Acetylenedicarboxylic acid, or butynedioic acid
  * Squaric acid, or quadratic acid
  