Phosphotungstic acid hydrate, ROTI®METIC 99,995 % (4N5), Molar mass (M) 2880,17 + x H2O g/mol, Boiling point (bp) 107,9 °C, CAS No. [12501-23-4], UN-Nr. 3260, EG-Nr. 603-020-3, Empirical formula H3PO4 · 12 WO3 · x H2O