Flexi Says: Salt, or sodium chloride (NaCl), is an ionic compound. When it dissolves in water, it separates into positive sodium ions (Na+) and negative chloride ions (Cl-). The negative oxygen ends of water molecules attract the positive sodium ions, and the positive hydrogen ends of water molecules attract the negative chloride ions. These forces of attraction pull the ions apart. Solid sodium chloride has a systematic geometric pattern of sodium and chloride ions. The ions can vibrate in their own position. As solid sodium chloride is heated the increase in energy makes the ions to vibrate greatly. At the melting point, these ions obtain enough energy to move out of crystal lattice. The result is molten sodium sodium chloride in which the ions are free to move about. Electrolysis of aqueous sodium chloride solution gives chlorine gas at anode and hydrogen gas at cathode. Whereas electrolysis of molten sodium chloride yields chlorine gas at anode but liquid sodium metal at cathode.
