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Question
Two ores A and B were taken. On heating ore A gives CO2 whereas, ore B gives SO2. What steps will you take to convert them into metals?
Solution
Ore A gives carbon dioxide on heating that means it is a carbonate ore. For the extraction of metal, ore A is first calcined and then reduced to get the pure metal.
Calcination: Ore A is heated in the absence of air below its melting point to get the oxide of the corresponding metal.
`"ACO"_3overset("Heat")(->) "AO" + "CO"_2`
Reduction: The metal oxide formed after the calcination process is further reduced with coke to get pure metal.
`"AO" + "C" overset("Heat")(->) "A" + "CO"`
Ore B gives sulphur dioxide on heating that means it is a sulphide ore. For the extraction of metal, ore B is first roasted and then reduced to get the pure metal.
Roasting: Ore B is heated in the presence of air below its melting point to get the oxide of the corresponding metal.
`2"BS" + 3"O"_3 overset("Heat")(->) 2"BO" + 2"SO"_2`
Reduction: The metal oxide formed after roasting is further reduced to with carbon to get pure metal.
`"BO" + "C" overset("Heat")(->) "B" + "CO"`
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