Acid ferric orthophosphate, Fe2O3.2P2O5.8H2O or (FePO4.H3PO4)2.5H2O, is obtained in the form of pink crystals when ferric phosphate is dissolved in excess of phosphoric acid and the solution concentrated over sulphuric acid.3 When boiled with water, neutral ferric orthophosphate, FePO4.2H2O, results. |