Ammonium phosphate

Ammonium phosphate is the inorganic compound with the formula (NH4)3PO4. It is the ammonium salt of orthophosphoric acid. A related "double salt", (NH4)3PO4.(NH4)2HPO4 is also recognized but is impractical use. Both triammonium salts evolve ammonia. In contrast to the unstable nature of the triammonium salts, the diammonium phosphate (NH4)2HPO4 and monoammonium salt (NH4)H2PO4 are stable materials that are commonly used as fertilizers to provide plants with fixed nitrogen and phosphorus.