K2[PtCl6] + 5KNO2 + H2O K2[Pt(NO2)4] + KNO3 + 4KCl + 2HCl
Potassium hexachloridoplatinate(IV) react with potassium nitrite and water to produce potassium tetranitroplatinate(VI), potassium nitrate , potassium chloride and hydrogen chloride. This reaction takes place at a temperature near 50°C.