The reactivity series of metals - carbon and hydrogen are non-metals, shown for comparison

So, oxygen is produced at the anode. Negative electrode - cathode. Positively charged H + and metal ions are attracted to the negative electrode but only one will gain electrons. Either hydrogen gas or metal will be produced. If the metal is above hydrogen in the reactivity series: The ions of the more reactive metal remain in solution

Explore electrolysis and charge transfer for IGCSE Chemistry. Learn about ionic compounds decomposing with electricity and the reactions at the electrodes.

The electrochemical series can be thought of as an extended, and slightly modified, reactivity series. All you really need to know as far as electrolysis is concerned is: The higher up the electrochemical series something on the right-hand side of the equilibrium is, the more readily it will lose electrons.

If the anion is a halide, the equivalent halogen will form at the anode; otherwise, oxygen gas will form. The reactivity series can be used to predict which materials will be inert; if the electrode material is less reactive than elements that make up the salt, the electrode will be unreactive during electrolysis.