In the extraction of zinc from zinc blende (ZnS), the first step is: MCQ with Answer and Explanation

In the extraction of zinc from zinc blende (ZnS), the first step is:
A. Smelting with coke
B. Roasting in air
C. Electrolysis
D. Leaching with NaOH
Answer: Option B
Solution (By JKExamLibrary)
Zinc blende (ZnS) is first concentrated by froth flotation, then roasted in excess air to convert it to ZnO: 2ZnS + 3O₂ → 2ZnO + 2SO₂. ZnO is then reduced with coke at high temperature (smelting) or dissolved in H₂SO₄ and electrolyzed. Roasting is typical for sulfide ores to remove sulfur as SO₂.

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