https://www.wikiwand.com/en/Reactivity_series

http://www.bbc.co.uk/education/guides/zqjsgk7/revision

The reactivity series allows us to predict how metals will react. A more reactive metal will displace a less reactive metal from a compound.

Displacement reactions of metal oxides

http://www.bbc.co.uk/education/guides/zqjsgk7/revision/2

A more reactive metal will displace a less reactive metal from a compound.

The Thermite reaction is a good example of this. It is used to produce white hot molten (liquid) iron for Welding

Displacement reactions of solutions

A more reactive metal will displace a less reactive metal from a solution of one of its salts.