An investigation on calcium (II) oxalate as solubility and universal standard

The investigation on calcium (II) oxalate is carried out in order to study its solubility in different ionic media. In the same conditions the protonation constants of oxalate and the stability of complex species have been determined. As the stoichiometric composition of the solid calcium (II) oxalate prepared for the investigation was accurately checked, the salt CaC2O4 x H2O is proposed as universal (chelometry, redox, acidimetry) standard. Results of titrations support this possibility.