Question

How is magnesium chloride formed by the transfer of electrons? Why does the solution of magnesium chloride conduct electricity?

Answer 1

Hint: Magnesium chloride is an ionic compound. Now you can easily write the answers for both parts.

Complete step by step answer:
Lets look at electronic configuration of each element Mg and Cl:
${ Mg }_{ 12 }$ - ${ 1s }^{ 2 }{ 2s }^{ 2 }{ 2p }^{ 6 }{ 3s }^{ 2 }$
${ Cl }_{ 17 }$ - ${ 1s }^{ 2 }{ 2s }^{ 2 }{ 2p }^{ 6 }{ 3s }^{ 2 }{ 3p }^{ 5 }$
Here we can see that Mg which is a metal loses two electrons and provides two electrons to each of two Cl non-metals (one to each).
Oxidation occurs at Magnesium :
            Mg $\rightarrow$ ${ Mg }^{ 2+ }$ + 2${ e }^{ - }$ ( e for electrons )
Reduction occurs at Chlorine :
Cl + ${ e }^{ - }$ $\rightarrow$ ${ Cl }^{ - }$

And the complete reaction is
${ Mg }^{ 2+ } + 2{ Cl }^{ - } \rightarrow { MgCl }_{ 2 }$
Hence ${ MgCl }_{ 2 }$ is formed by the transfer of electrons from electron rich to electron deficient species.
Magnesium chloride only conducts electricity when in molten or liquid state. It is an ionic compound and in liquid state it releases its ions when enables them to conduct electricity. When current is passed through its solution, the process of electrolysis starts because the solution of Magnesium Chloride starts to ionize.

Note: Magnesium Chloride, an inorganic compound consisting of one magnesium and two chloride ions. The compound is used as a source of magnesium ions in medicine which is important for many cellular activities.