Ionic compounds have high melting points and are solid at room temperature.
Ionic compounds can conduct electricity when they are dissolved in solution or molten.
Ionic compounds have high melting points and boiling points because of the many strong electrostatic forces of attraction between oppositely charged ions in the giant lattice structure. Ionic compounds will conduct electricity when molten or lattice because the ions are able to move freely around in the liquids.
Ionic compounds will not conduct electricity as they are fixed in a lattice. They vibrate whe he electrides are placed in but they cannot move around, so they don't conduct.
When dissolved NaCl does conduct electricity. The water molecules sperate ions from the lattice, the ions are then free to move around. Therefore, when the electrodes are placed in the solution the protons and electrons are drawn to the oppositely charged electrode.
Molten compounds, the high temperatures provide enough nergy to overcome the many strong attractive forces between ions. They are free to move around withi the compound, this allows it to conduct electricity.