Extraction of iron from zine blende is achieved by

Options

A. Electrolytic reduction
B. Roasting followed by reduction with carbon
C. Roasting followed by reduction with other metal
D. Roasting followed by self-reduction

Answer

B

Explanation

When zinc blende is used, the powdered ore is concentrated by froth floatation process. The concentrated ore is heated in excess of oxygen at about `900^@ C`. Zinc sulphide is oxidised to zinx oxide. If some of the ore is oxidised to zinc sulphide, it also decomposes at `900^@ C` into `ZnO`. This is roasting. It is followed by reduction. The reaction that takews place during reduction is the conversion of the oxide into metal with the help of carbon.
`2 ZnS + 3O_(2) overset (Delta) rarr 2 ZnO + 2SO_(2) uarr`
`ZnSO_(4) overset (Delta) rarr ZnO + SO_(2) + (1)/(2) O_(2) uarr`
`ZnO + C overset (Delta) rarr Zn + CO uarr`.