Crushing and grinding of ore followed by separation of useful mineral from earthy impurities is called
AConcentration (dressing) of ore
BReduction of ore by carbon
CCalcination of ore in absence of air
DRoasting of ore in presence of air
Answer & Solution
Correct answer: A. Concentration (dressing) of ore
1. The chapter section on extraction lists the first step.
2. After mining, the ore is crushed and the useful part is concentrated.
3. Gangue (earthy impurity) is separated.
4. This is called concentration or dressing.
_Source: Selina Concise Chemistry Class 10, Ch 7 Metallurgy (Mistral OCR'd PDF), section on concentration of ore_
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