Which method of metal refining is generally used when a metal of high degree of purity is needed?
Write a chemical equation for the roasting of an ore of each type.
In roasting ore is heated in the presence of excess of oxygen or air. This method is employed for sulphide ores. Example: ZnS (sphalerite) and Cu2S (chalcocite)
The chemical equation:
2ZnS +3O2 → 2ZnO + 2SO2
2Cu2S +3O2 → 2Cu2O + 2SO2
Explain the following:
Partial roasting of sulphide ore is done in the metallurgy of copper.