K2[OsO2(OH)4] + 8KCN K4[Os(CN)6] + 2KOCN + 4KOH
Potassium tetrahydroxodioxoosmate(VI) react with potassium cyanide to produce hexacyanoosmate(II) potassium, potassium cyanate and potassium hydroxide. The reaction takes place in a boiling solution in the concentrated solution potassium hydroxide.