2CrO3 + 8H2O2 + 6KCN → 2K3[Cr(O2)4] + C2N2 + 4HCN + 6H2O
Chromium trioxide react with hydrogen peroxide and potassium cyanate to produce potassium tetraperoxochromate(V), cyanogen, hydrogen cyanide and water. This reaction takes place at a temperature near 0°C.