Question

Metallic magnesium is prepared by.

• A. Reduction of $MgO$ by coke
• B. Electrolysis of aqueous solution of $Mg(NO_{3})$
• C. Displacement of $Mg$ by iron from $MgSO_{4}$ solution
• D. Electrolysis of molten $MgCl_{2}$

Answer 1

Answer: (D)

Electrolysis of molten $MgCl_{2}$

Answer 2

$\underset{(\text{Molten})}{MgCl_{2}}\overset{\quad Electrolysis\quad}{\rightarrow}\underset{\text{Cation}}{Mg^{+ 2}} + \underset{\text{Anion}}{2Cl}$

Anode – $2Cl^{-} \rightarrow 2Cl + 2e^{-}$,$Cl + Cl \rightarrow Cl_{2}$

Cathode – $Mg^{+ 2} + 2e^{-} \rightarrow Mg$.