Chapter 7, Problem 46A

Interpretation Introduction

Interpretation:The reason for molten ${\text{MgCl}}_{\text{2}}$ to conduct an electric current but not crystalline ${\text{MgCl}}_{\text{2}}$ needs to be explained.

Concept Introduction:

A compound that can completely dissociate into ions in water can conduct electricity and a compound that cannot dissociate does not conduct electricity.

Answer to Problem 46A

Ions are bound tightly when ionic compounds are in the solid state.

Explanation of Solution

Whether a compound can conduct electricity or not can be easily determined by identifying its composition. Here, molten ${\text{MgCl}}_{\text{2}}$ is present in the form of ions in water that is ${\text{Mg}}^{2+}$ and 2 ${\text{Cl}}^{-}$ , thus, it can conduct electricity. Ionic compounds do not conduct electricity when they are solid. Because the ions are firmly bound to the lattice in the solid state, and thus,magnesium chloride will not conduct electricity when it is solid.