A phosphate is a salt that is prepared from orthophosphoric acid. Phosphates are usually sodium salts but can also include potassium, calcium, magnesium, and ammonium salts as well. The phosphates have a wide range of applications in the chemical industry. The mono-, di-, and tri-metallic salts of phosphoric acid, for example, are used extensively in many industrial applications. Polyphosphates are a group of phosphates that are created from polymeric chemical compounds. These compounds are produced from the condensation reactions of several phosphoric acid molecules. The chemical formula for the phosphate ion is PO₄^3-. The phosphate ion is a polyatomic ion, in other words, a group of covalently bonded atoms that together carry an electrical charge. Polyatomic ions can combine with oppositely charged ions, through ionic bonding. When they do so, they form ionic compounds.

Because the phosphates have many industrial applications, they are produced in great quantities...