Zinc sulphate CAS#7733-02-0
Zinc sulfate (ZnSO₄), also referred to as white vitriol or zinc alum, occurs as colorless or white rhombic crystals or powder under ambient temperature. It delivers an astringent taste and dissolves readily in water to form an acidic aqueous solution. It is sparingly soluble in ethanol and glycerol.
High‑purity zinc sulfate will not turn yellow upon long‑term exposure to air. When kept in dry air, it effloresces and converts into a white powdery form. It exists in multiple hydrated forms: zinc sulfate heptahydrate remains the stable hydrate in aqueous equilibrium from 0‑39 °C; zinc sulfate hexahydrate is stable between 39‑60 °C; and zinc sulfate monohydrate predominates within 60‑100 °C.
All hydrate variants lose their crystal water completely when heated to 280 °C. It decomposes into zinc oxysulfate at 680 °C, undergoes further breakdown above 750 °C, and ultimately decomposes into zinc oxide and sulfur trioxide at approximately 930 °C. ZnSO₄·7H₂O can form mixed crystals with MSO₄·7H₂O (M=Mg, Fe, Mn, Co, Ni) within certain concentration ranges.
Zinc sulphate Chemical Properties
| Melting point | 100°C |
| Boiling point | 105°C (estimate) |
| density | 1.31 g/mL at 20 °C |
| storage temp. | Store at +15°C to +25°C. |
| solubility | H2O: soluble |
| form | Liquid |
| color | Colorless |
| PH | 4.0±0.5 |
| Water Solubility | Soluble |
| λmax | λ: 260 nm Amax: <0.02 λ: 280 nm Amax: <0.02 |
| Merck | 14,10159 |
| LogP | -1.031 (est) |
| CAS DataBase Reference | 7733-02-0(CAS DataBase Reference) |
| NIST Chemistry Reference | Zinc sulfate(7733-02-0) |
| EPA Substance Registry System | Zinc sulfate (7733-02-0) |
