Explain extraction of magnesium by electrolytic reduction method.

Explanation

Magnesium metal is obtained by passing electricity through molten magnesium chloride.
the reactions are :
`undersetunderset("Chloride")("molten magnesium")(MgCl_(2)) overset("heat")to Mg^(2+) + 2Cl^(-)`
At cathode : `undersetunderset("ion")("Magnesium")(Mg^(2+)) + 2e^-) to undersetunderset("metal")("magnesium")(Mg)` (reduction)
At anode :
`2Cl^(-) + Cl_(2) + 2e^(-)` (oxidation)
Net overall reaction may be written as :
`undersetunderset("Chloride")("Magnesium")(MgCl_(2))("molten")overset("electricity")toundersetunderset("(at cathode)")("magnesium")(Mg) + undersetunderset("(at anode)")("chlorine gas")(Cl_(2))`
Magnesium metal is obtained at cathode and chlorine gas is evolved at anode.
Thus, during electrolytic reduction of molten salts, the corresponding metal is obtained at the cathode (the negative electrode).