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Ammonium hydrosulfide is the chemical compound with the formula (NH4)SH. It is the salt derived from the ammonium cation and the hydrosulfide anion. By passing hydrogen sulfide mixed with a slight excess of ammonia gives the colourless, micaceous crystals. It dissolves readily in water but is partially dissociated in solution. The compound is encountered mainly as a solution, not as the salt. It is a corrosive agent in oil refineries, where it is generated in the handling of hydrogen sulfide.
In addition to water and ammonia, the clouds in the atmospheres of the gas giant planets contain ammonium sulfides. The reddish-brownish clouds, which have been exposed to prolonged sunlight are attributed to polysulfides.
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