Ions in molton ionic compounds or in solutions are free to move and so can conduct electricity. The compounds are broken down into elements by electrolysis.
Positive ions are attracted to the negative electrode (annode) where they gain and lose electrons (reduction) and negative ions lose electrons at the positive electrode (Cathode)(oxidations).
Electrolysis- sodium chloride and copper
Reactions at electrodes depend on the ions that are present, their concentrations and what the electrode is made from.
Electrolysis of sodium chloride solution is used in industry to produce chlorine, sodium hydroxide and hydrogen.
Copper can be purified by electrolysis using copper electrodes in a solution containing copper ions.
Reactions at electrodes can be represented by half equations.