Group 0 – the noble gases
Helium, neon, argon, krypton and xenon are in Group 0. They all have a full outer electron shell which means they are already stable and so do not need to lose or gain electrons. This means that they are chemically Unreactive. (ie they do not react with anything under normal circumstances).
The noble gases have the following properties in common:
- they are non-metals
- they are very unreactive gases
- they are colourless
- they exist as single atoms (they are monatomic)
The atoms of the noble gases have full outer shells of electrons. Helium atoms have two electrons in their outer shell. The atoms of the other noble gases have eight electrons in their outer shells.
Uses of the noble gases
The uses of the noble gases are usually linked to the fact that they are inert, or to their tendency to give off light when an electric current is passed through them.
| Noble gas | Uses |
| Helium | Party balloons, weather balloons, airships |
| Neon | Red neon signs, lasers |
| Argon | Shielding gas for welding, surrounding the filament in an old-fashioned lightbulb |
| Noble gas | Helium |
|---|---|
| Uses | Party balloons, weather balloons, airships |
| Noble gas | Neon |
|---|---|
| Uses | Red neon signs, lasers |
| Noble gas | Argon |
|---|---|
| Uses | Shielding gas for welding, surrounding the filament in an old-fashioned lightbulb |