Question

Difference between roasting and calcination explain thw two process with the help of suitable chemical equation taking the example of zinc

Answer 1

roasting
roasting is done for sulphide ores
it is done with excess of oxygen
ZnS+O2---- ZnO+S


calcination
calcination is done for carbonate ores
it is done with Limited oxygen

ZnCO3+O2 ----- ZnO +CO2

Answer 2

roasting is done for sulphide ores with excess amount of O2
calcination is done for carbonate ores with limited amount of CO2