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Question
Explain the following reaction with the balanced equation.
Zinc sulphide is heated strongly in excess of air
Solution
Zinc sulphide is heated strongly in excess of air to convert it to zinc oxide. This process is called roasting.
\[\ce{\underset{\text{Zinc sulphide}}{2ZnS_{(s)}} + 3O_{2(g)} -> \underset{\text{Zinc oxide}}{2ZnO_{(s)}} + \underset{\text{Sulphur dioxide}}{2SO_2↑}}\]
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