Preparation of ammonium pentasulfide
Twenty-five millilitres of concentrated ammonia are saturated with hydrogen sulfide gas while cooling in ice. When no more gas is absorbed 25 ml more of the ammonia water is added. The ammonium sulfide solution is warmed to about 35° C and then 25 g of finely powdered roll sulfur are stirred in. When no more dissolves (30-60 minutes), the yellow solution is filtered into 60 ml of 95% alcohol and allowed to stand in a stoppered flask overnight in the refrigerator. The crystals are filtered by suction and washed with alcohol and ether. They are dried in vacuo over lime covered with a very small amount of solid ammonium chloride. The yield of ammonium pentasulfide is 40 g, which decomposes on long-standing, especially in air, with the deposition of sulfur.
Inorganic laboratory preparations, by G. G. Schlessinger, 28-29, 1962
azanium pentasulfide, Ammonium sulfide ((NH4)2(S5)), Ammonium pentasulfide, AC1MHZZE, Diammonium pentasulphide, EINECS 235-225-5, 12135-77-2, 101900-58-7, 137916-01-9, 145849-26-9, 168281-91-2, 61320-62-5