Why do ionic compounds conduct electricity in a molten state?

Ionic compounds conduct electricity in the molten state because their ions are free to move and carry electric charge. In a solid state, the ions in an ionic compound are held in a rigid lattice structure by strong electrostatic forces of attraction between the positively and negatively charged ions. These forces prevent the ions from moving and carrying electric charge.

However, when an ionic compound is melted, the strong electrostatic forces are overcome, and the lattice structure breaks down. As a result, the ions become mobile and are able to move freely within the molten liquid. Since the ions carry an electric charge, their movement in response to an electric field allows for the flow of electric current.

In the molten state, the liquid allows for the movement of both positive and negative ions, enabling the flow of electric charge. This property is why molten ionic compounds, such as molten salts, are often used as electrolytes in various industrial processes, such as electrolysis and electroplating.