DAP (Diammonium Phosphate)

Diammonium phosphate (DAP) (chemical formula (NH4)2HPO4, IUPAC name diammonium hydrogen phosphate) is one of a series of water-soluble ammonium phosphate salts produced when ammonia reacts with phosphoric acid. Solid diammonium phosphate exhibits a dissociation pressure of ammonia. DAP is primarily used as a fertilizer. Upon application, it temporarily increases the soil pH. However, over time, the treated soil tends to become more acidic due to the nitrification of the ammonium present in DAP. It is incompatible with alkaline chemicals, as the ammonium ion in DAP is prone to converting to ammonia in high-pH environments.