Why do ionic compounds conduct electric current when they are melted or dissolved in water?

• A. Because their ions are free to move and carry charge.
• B. Because their molecules form covalent bonds with water.
• C. Because their ions become neutral in solution.
• D. Because their atoms gain electrons from water.

Answer: (A)

Verified step by step guidance

1. Understand that ionic compounds are made up of positive and negative ions held together in a rigid lattice structure in the solid state.
2. Recognize that in the solid state, these ions are fixed in place and cannot move freely, so the solid ionic compound does not conduct electricity.
3. When an ionic compound is melted or dissolved in water, the rigid lattice breaks down, allowing the ions to separate and move freely.
4. Free-moving ions in the liquid or aqueous state can carry electric charge through the substance, enabling electrical conductivity.
5. Therefore, the key reason ionic compounds conduct electricity when melted or dissolved is that their ions are free to move and carry charge.