Question

How does the electrical conductivity of ionic compounds change?

Answer 1

Ionic compounds do not conduct electricity when they are solid. They conduct electricity only if their ions are free to move — in the molten state or in aqueous solution.

You can read about it in

http://socratic.org/questions/why-don-t-ionic-compounds-have-electrical-conductivity-as-a-solid-but-they-do-as

Hope this helps.