Calcination is the heating of an ore
AIn the presence of nitrogen
BIn the presence of air
CWith chlorine gas only
DIn the absence of air
Answer & Solution
Correct answer: D. In the absence of air
1. The chapter compares calcination with roasting.
2. Calcination heats the ore strongly in absence of air.
3. Moisture and volatile impurities escape.
4. Carbonates decompose to oxides.
_Source: Selina Concise Chemistry Class 10, Ch 7 Metallurgy (Mistral OCR'd PDF), section on calcination_
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