alleryStart learning →Roasting differs from calcination in that roasting is the heating of an ore
Ain the complete absence of any air
Bstrongly in the presence of excess air
Cwith carbon as a reducing agent
Dby passing electric current
Answer & Solution
Correct answer: B. strongly in the presence of excess air
1. Both convert ores to oxides before reduction.
2. **Roasting** heats a sulphide ore strongly in **excess air**: 2ZnS + 3O₂ → 2ZnO + 2SO₂.
3. Calcination heats a carbonate ore in limited air: ZnCO₃ → ZnO + CO₂.
_Source: Karnataka SSLC (KSEEB) Class 10 Science, Ch3 'Metals and Non-metals', §3.4.4_
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