It is widely used in fertilizers (as phosphate salts) rust removal and metal treatment food additives (e.g. in soft drinks for acidity) and in detergents as a builder.

Its primary purpose is to provide acidity for pH adjustment form stable phosphate salts or esters in synthesis and act as a sequestering agent for metal ions in cleaning and industrial processes.

Phosphoric acid (H3PO4) is a colorless to clear viscous liquid or white crystalline solid (depending on concentration and temperature) featuring a central phosphorus atom bonded to one double-bonded oxygen and three hydroxyl groups in a tetrahedral geometry.