Which type of compound conducts electricity when dissolved in water?

• A. Covalent compound
• B. Ionic compound
• C. Metallic compound
• D. Molecular compound

Answer: (B)

Electric conductivity in water comes from moving charged particles. Ionic compounds are made of positively and negatively charged ions held together by strong ionic bonds. When they dissolve, the solid lattice breaks apart and the ions separate and become surrounded by water (hydration). These free ions can move throughout the solution, carrying electric current, so the solution conducts electricity.

Covalent (molecular) compounds, on the other hand, are composed of neutral molecules. In water they mostly remain as intact molecules rather than forming mobile ions, so they don’t typically conduct electricity well. Metallic compounds conduct electricity in the solid state because of a sea of delocalized electrons, but they don’t dissolve in water to form an ion-conducting solution.

So the type that conducts electricity when dissolved in water is the ionic compound.