(NH4)2[PtCl6] + H2C2O4 (NH4)2[PtCl4] + 2CO2 + 2HCl
Ammonium hexachloridoplatinate(IV) react with oxalic acid to produce tetrachloridoplatinate(II) ammonium, carbon dioxide and hydrogen chloride. Ammonium hexachloridoplatinate(IV) in the suspension form. Oxalic acid - concentrated solution. The reaction takes place in a boiling solution.