Tags: Chemical Compound, Chemical Substance.
Phosphotungstic acid (PTA) tungstophosphoric acid (TPA) is a heteropoly acid with the chemical formula H3PW12O40. It is normally present as a hydrate. EPTA is the name of ethanolic phosphotungstic acid its alcohol solution used in biology. It has the appearance of small colorless-grayish or slightly yellow-green crystals with melting point 89 °C (24 H2O hydrate). It is odorless and soluble in water (200 g/100 ml). It is not especially toxic but is a mild acidic irritant.
