Explain with example - calcination and roasting

Roasting : It is the process of converting an ores to oxide by strongly heating it in the presence of excess of air . For example sulphide ores are converted into their respective oxide by heating in the presence of air.

eg : 2 ZnS +3O2 -------->  2 ZnO + 2SO2 .

Calcination : It is the process of converting an ores to oxide by strongly heating it in limited air . For example carbonate ores are converted into the oxide by heating in the absence of air.

eg : ZnCO3 -----> ZnO + CO2

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 the process of conversion of carbonate ore into mettalic oxide by heating it strongly in the presence of air is called calcination

eg:znco3---->zno+co2.

the process of conversion of sulphide ore into mattalic oxides in the absence of air is called roasting

eg:znso4----->zn+so2

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Hie...,

Roasting : The sulphide ores are converted into oxides by heating strongly in the presence of excess of air. this process is called roasting , in this sulphur dioxide is form .

ex: 2Zns(s) + 3O6^2(g) when heated it gives 2ZnO(s) + 2 SO^2(g)

 

Calcination: The carbonate ores are changed into oxides by heating strongly in limited air. This process is called calcination., in this Carbon dioxide is form.

ex: ZnCO^3(s) when heated it gives ZnO(s) + CO^2(g)

^2 nd ^3 ..this means that the no..are in squares nd cubes..!!

H0pe this will help u...!!

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