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Phosphoric acid

Phosphoric acid is a mineral acid with the chemical formula H3PO4. Its main uses are in fertilizers and detergents, and in cleaning and rust-proofing agents. It is also used to acidify foods and beverages such as cola. It is prepared by adding sulphuric acid to calcium phosphate rock.

In its anhydrous form the acid is a white solid. In aqueous solution, the acid releases three hydronium (H+) ions.

The anion associated with phosphoric acid is called the phosphate ion, and is found pervasively in biology, especially in the compounds derived from phosphorylated sugars, such as DNA and RNA and adenosine triphosphate (e.g. ATP).