Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!

Home > Science > Chemical and material behaviour > Atoms and elements


Atoms and elements


Chemical symbols

Each element is given its own chemical symbol, like O for oxygen and Cl for chlorine. Chemical symbols are usually one or two letters long, but sometimes three letters are used.

Every chemical symbol starts with a capital letter, with the second or third letters written in lower case.

For example, Mg is the correct symbol for magnesium, but mg, mG and MG are wrong.

Take care to write chemical symbols correctly

Mg mg mG MG
A green tick a red cross a red cross a red cross

Symbols and names

Sometimes it is easy to tell which element a symbol stands for. For example, O stands for oxygen and Li stands for lithium.

But sometimes the symbol comes from a name for the element that is not an English word.For example, W stands for tungsten (from the word wolfram) and Na stands for sodium (from the word natrium).

The reason is that the same chemical symbols are used all over the world, no matter which language is spoken, which makes them most useful.


Atoms and elements activity

Brave the elements!



Use your knowledge to help Spherox find his way home.

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.