.4 Electrolysis of aqueous solutions

• The ions discharged when an aqueous solution is electrolysed using inert electrodes depend on the relative reactivity of the elements involved
• At the negative electrode (cathode), hydrogen is produced if the metal is more reactive than hydrogen
• At the positive electrode (anode), oxygen is produced unless the solution contains halide ions when the halogen is produced.
• This happens because in the aqueous solution water molecules break down producing hydrogen ions and hydroxide ions that are discharged.