Zyra's website //// Periodic Table //// Science //// Site Index

Inert Gases

or Noble Gases, Group 0 elements


The Inert Gases are a set of elements which are in the Group 0 vertical column on the right edge of the Periodic Table. They have a complete outer shell of electrons and a valency of zero, and are therefore are inert, forming almost no chemical compounds. Here's the list of Inert Gases...

Helium - element 2, atomic weight 4.003

Neon - element 10, atomic weight 20.183

Argon - element 18, atomic weight 39.948

Krypton - element 36, atomic weight 83.80

Xenon - element 54, atomic weight 131.3

Radon - element 86, atomic weight 222

Ununoctium - element 118, atomic weight unknown. Also see Extended Periodic Table

Although the Inert Gases don't form compounds except for in some very unusual situations, they have interesting physical properties. For example, electrically they can be excited by energy and give off light of interesting colours according to the element.

The list of Inert or Noble Gases is always in this order [Helium, Neon, Argon, Krypton, Xenon, Radon] as that's the order of weight. The lightest being Helium, and then so-on down the list. Helium and Neon are lighter than air. Krypton and Xenon are heavier than air. And Radon has such a heavy nucleus that it is radioactive and tends to decay spontaneously into a sequence of various other things including Polonium, Bismuth, and Radioactive Lead.

Ununoctium would be an inert gas that would be a solid at room temperature. However, it is very unstable, and even if someone were to generate some, it would soon disappear.


Nitrogen is not an Inert Gas, but it is a gas which is quite stable.