Diphosphate

Diammonium phosphate (DAP) (chemical formula (NH₄)₂HPO₄, IUPAC name diammonium hydrogen phosphate) is one of a series of water-soluble ammonium phosphate salts which can be produced when ammonia reacts with phosphoric acid.

Dicalcium phosphate, also known as calcium monohydrogen phosphate, is a dibasic calcium phosphate. It is usually found as the dihydrate, with the chemical formula of CaHPO₄ H₂O, but it can be thermally converted to the anhydrous form. It is practically insoluble in water.

Dipotassium phosphate (K₂HPO₄) - also phosphoric acid, dipotassium salt; dipotassium hydrogen orthophosphate; potassium phosphate, dibasic - is a highly water-soluble salt which is often used as a fertilizer, food additive and buffering agent.

Disodium hydrogen phosphate (Na₂HPO₄) is a sodium salt of phosphoric acid. It is a white powder that is highly hygroscopic and water soluble.[1] It is therefore used commercially as an anti-caking additive in powdered products.