Ammonium Sulfate

Ammonium sulfate (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen as ammonium cations, and 24% sulfur as sulfate anions. In fertilizer the purpose of the sulfate is to reduce the soil pH.

Ammonium sulfate is used largely as an artificial fertilizer for alkaline soils. In the soil, the sulfate ion is released and forms sulfuric acid, lowering the pH balance of the soil (as do other sulfate compounds such as aluminum sulfate), while contributing essential nitrogen for plant growth.