Question

11 (a) Explain why is molten sodium chloride decomposed by electric current while solid sodium chloride is not.

Answer 1

Ionic Theory

• In solutions, electrolytes are present in the form of ions and permits the flow of current through them.
• Movement of ions is responsible for the flow of current.
• Sodium chloride$\left(\mathrm{NaCl}\right)$ is an electrolyte that will conduct electricity either in aqueous solutions or in molten state.

Molten and solid form of Sodium chloride $\left(\mathrm{NaCl}\right)$

• Sodium chloride is an ionic compound that involves the presence of sodium$\left({\mathrm{Na}}^{+}\right)$ and chloride$\left({\mathrm{Cl}}^{-}\right)$ ions.
• In molten form, these ions are free to move. Therefore, molten sodium chloride is decomposed by electric current.
• In solid-state, the ions are not allowed to move freely, and due to this solid sodium chloride cannot be decomposed by electric current.