Give the steps involved in the extraction of metals of low and medium reactivity from their respective sulphide ores.
During extraction of metals of low and medium reactivity, a respective sulphide ore is first heated in air. This helps in obtaining oxide of metal. It is easier to extract a metal from its oxide rather than from its sulphide. Hence, this step is used. Mercury is a metal of low reactivity. Mercury sulphide (cinnabar) is heated in air. Mercury sulphide gets oxidized to produce mercury oxide.
2HgS +3O2 → 2HgO + 2SO2
After that, mercury oxide is reduced to obtain mercury.
2HgO → 2Hg + O2
Zinc is a metal of medium reactivity. It is found as zinc blende (ZnS).
Zinc blende is roasted to obtain zinc oxide. After that, zinc oxide is reduced to obtain pure zinc.
2ZnS + 3O2 → ZnO + 2SO2
After that, mercury oxide is reduced to obtain mercury.
ZnO + C → Zn + CO
