2K4[Fe(CN)6] + 4H2SO4 + 4KNO3 → 2K2[Fe(NO)(CN)5] + 2NO + C2N2 + 4K2SO4 + 4H2O
Potassium hexacyanoferrate(II) react with sulfuric acid and potassium nitrate to produce potassium pentacyanonitrosoferrate(II), nitric oxide, cyanogen, potassium sulfate and water.