Zinc sulphate heptahydrate, min. 97 %, extra pure, Molar mass (M) 287,54 g/mol, Density (D) 1,97 g/cm³, CAS No. [7446-20-0], UN-Nr. 3077, EG-Nr. 231-793-3, Empirical formula ZnSO4 · 7 H2O