RuO4 + 2NH4Cl + 8HCl → (NH4)2[RuCl6] + 2Cl2 + 4H2O
Ruthenium(VIII) oxide react with ammonium chloride and hydrogen chloride to produce ammonium hexachloridoruthenate(IV), chlorine and water. Ammonium chloride and hydrogen chloride - concentrated solutions.