In the extraction of Iron from Haematite Fe2O3, the ore is calcinated before ______ .
True
Haematite also contains traces of FeO and Fe3O4 . In the smelting process, where the iron oxide is reduced to metallic molten iron, slag is formed by the action of SiO2 on CaO. In case there are traces of FeO or Fe3O4 , then SiO2 can combine with FeO and form FeSiO3 and this would result in the loss of percentage of Iron. Hence Iron ore is calcinated just before smelting and this converts the traces of FeO or Fe3O4 to Fe2O3 .
Also moisture is removed as:
Fe2O3.xH2O(s)→Fe2O3(s)+xH2O