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प्रश्न
Explain with reason:
Roasting is carried out on sulphide ores and not on carbonate ores.
उत्तर
Roasting provides oxygen to convert metallic sulphides into metallic oxide and \[\ce{SO2}\] which takes place when heated in excess of air.
Carbonate is converted into oxide by loss of \[\ce{CO2}\] which takes place in the absence of air and when heated strongly.
\[\ce{CaCO3 ->[\Delta] CaO + CO2}\]
\[\ce{2PbS + 3O2 -> 2PbO + 2SO2 ^}\]
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