Question

In the extraction of zinc from zinc blende:
How is impure zinc finally electro-refined?

Answer 1

Electro refining of zinc:
Electrolyte used: $ZnS{O}_4$ solution containing a little $H_{2}S{O}_4$
Anode : Block of impure zinc
Cathode : Thin sheet of pure zinc.
On passing current pure zinc is obtained at cathode.
Anode reaction: $\underset{impure}{Zn}-2e^{-}\to Z{n}_{aq}^{2+}$
Cathode reaction: $Z{n}_{aq}^{2+}+2e^{-}\to \underset{puremetal}{Zn}$