Question

Redox reaction takes place (in the extraction of $Mg$):

• A. in the electrolytic cell when fused $MgC{l}_2$ is subjected to electrolysis
• B. when fused $MgC{O}_3$ is heated
• C. when fused $MgC{O}_3$ is strongly heated
• D. none of the above

Answer 1

The correct option is A in the electrolytic cell when fused $MgC{l}_2$ is subjected to electrolysis

Electrolysis of fused magnesium chloride is carried out.
$MgC{l}_2\rightleftharpoons M{g}^{2+}+2C{l}^{-}$
At graphite anode: $2C{l}^{-}\to C{l}_2+2e^{-}$
At iron cathode: $M{g}^{2+}+2e^{-}\to Mg$.