What happens to ionic compounds when they are melted?

When ionic compounds are melted, the tightly packed lattice structure of ions breaks down, allowing the individual ions to move freely. This movement enables the melted ionic compound to conduct electricity. The free-moving ions can carry an electric current, which is a key characteristic of ionic compounds in a molten state.

In contrast, when ionic compounds are solid, their ions are fixed in place within the crystal lattice and cannot move freely, making them poor conductors of electricity. This is a fundamental property of ionic substances; in their solid form, they do not conduct electricity, but once melted, the ability to conduct electricity arises due to the mobility of the ions.