Reactivity Series

Metals have something in common when they undergo chemical reaction. They have electrons in their outermost shell that they are looking to get rid of.

For example, lithium has three electrons in total and one in its outer shell:

So, lithium becomes stable by losing the one electron in its outer shell.

Aluminium has 13 electrons in total and three in its outer shell:

So, aluminium becomes stable by losing three electrons.

There are metals that are reactive. This means that they easily undergo chemical reaction and form new substances. An example of a reactive metal is potassium.

There are also metals that are quite unreactive. This means that they do not easily undergo chemical reaction. An example of an unreactive metal is platinum.

If we ordered metals based on how reactive they are, we would get the reactivity series.

The reactivity series sorts metals in the order of their reactivity, with the most reactive element at the top and the least reactive at the bottom. So, potassium is a very reactive metal and the least reactive is platinum.