The reactivity series ranks metals by how readily they react. More reactive metals displace less reactive metals from their compounds and react with water.

When a chemical reaction occurs, energy is transferred to, or from, the surroundings. An exothermic reaction releases heat to the surroundings and an endothermic reaction absorbs heat from the surroundings.

Electrolysis involves using electricity to break down electrolytes. Electrolysis can be used to extract some metals, like aluminium, from their ore.