Ammonium sulfate (NH4)2SO4
Ammonium sulfate is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen and 24% sulfur by weight.
|Solubility in water at 20°C:||706 g/L|
Ammonium sulfate is made by treating ammonia, often as a by-product from coke ovens, with sulfuric acid:
2 NH3 + H2SO4 → (NH4)2SO4
Ammonium sulfate also is manufactured from gypsum (CaSO4·2H2O). Finely divided gypsum is added to an ammonium carbonate solution. Calcium carbonate precipitates as a solid, leaving ammonium sulfate in the solution.
(NH4)2CO3 + CaSO4 → (NH4)2SO4 + CaCO3