State and explain whether NaCl and Mg can conduct electricity in both the solid and molten states.

NaCl cannot conduct electricity in the solid state as the ions are held in an ionic lattice and therefore are not free to conduct. NaCl can conduct in the melt as the ions become mobile and therefore are free to move and carry a current.Mg contains delocalised electrons in both the solid and molten states, these electrons are free to move around the structure and conduct electricity.