... Zinc Sulfate Molecular formula------ZnSO4Molar mass-------161.47 g/mol (anhydrous) 179.47 g/mol (monohydrate) 287.53 g/mol (heptahydrate ... °C (heptahydrate) 70 °C, decomp (hexahydrate)Boiling point------740 °C (anhydrous) 280 °C, decomp (heptahydrate)Solubility in water------22 g/100 ... ml, anhydrous (20 ºC) 96.5 g/100mL, heptahydrate (20 °C) ...