Write the chemical reactions taking place in the extraction of zinc from zinc blende.

(N/A) The extraction of zinc from zinc blende $(ZnS)$ involves the following steps:
$(i)$ Concentration of ore: The ore is concentrated by the froth floatation process.
$(ii)$ Roasting: The concentrated ore is heated in a regular supply of air to convert it into zinc oxide.
$2 ZnS + 3 O_{2} \longrightarrow 2 ZnO + 2 SO_{2}$
$(iii)$ Reduction: Zinc oxide is reduced to zinc metal by heating it with coke.
$ZnO + C \xrightarrow{673 \ K} Zn + CO$
$(iv)$ Electrolytic Refining: The impure zinc is refined by electrolysis using an acidified solution of zinc sulphate $(ZnSO_{4})$ as the electrolyte,with impure zinc as the anode and pure zinc as the cathode.
Anode: $Zn \longrightarrow Zn^{2+} + 2e^{-}$
Cathode: $Zn^{2+} + 2e^{-} \longrightarrow Zn$