GCSE CHEMISTRY - What are the Noble Gases? - What are the Properties of the Noble Gases Helium, Neon, Argon, Krypton and Xenon? - What are the Group Trends of the Noble Gases?

What are the Noble Gases?

The noble gases are helium, neon, argon, krypton, xenon and radon.
Radon is radioactive. Radon-220 from rocks is a health hazard.
The noble gases are in group 0 on the right of the periodic table.
See the noble gases for shortcuts to the pages of this section.

What are the Properties of the Noble Gases?

1. The noble gases are almost entirely unreactive because
they all have a full outer shell of electrons and are
not interested in reacting with other substances. Substances
that are very unreactive are called chemically inert.

2. The noble gases are all colourless monatomic gases.
Monatomic means that they exist as single atoms. The forces
between the atoms are very weak (and so they are gases).

What are the Group Trends for the Noble Gases?

Going down group 0 from helium to radon, the noble gases

1. Have a higher density.

2. Have higher melting points and boiling points because the atoms
become heavier (bigger) and require more energy to melt or boil.