Group 18: The Noble Gases


Group 18 the Noble Gases are the name given to a collection of gases that exist in Group 18 at the very end of the periodic table. They are all non metals and exist as monoatomic gases which are relatively inert and unreactive due to their full outer shell of electrons.

Noble gases are a group of non metals in group 18 that are often described as chemically inert. Noble gases are highly unreactive due to their full outer shell of electrons. Having a full shell of 8 electrons means there is no need for the atom to lose or gain electrons. The noble gases have some of the highest ionisation energies in the periodic table due to their stable structure but some reactions are still possible. Xenon as a noble gas can be combined with fluorine to form xenon fluoride which is a stable compound which has more than 8 electrons in its outer shell as Xenon is able to accept more electrons in its outer shell.

Terms in section
Ionisation energy

Ionisation energy is the amount of energy required to remove an electron from an atom creating a positvely charged ion

Noble gases

Noble gases are very unreactive non metal elements found in group 18 of the periodic table. They do not react with other elements easily and are all gases.


Unreactive describes an element or atom that will not change because of another as they are quite stable

Non metals

Non metals are located mainly on the right hand side of the periodic table and comprise of covalently bonded compounds. Non metals share electrons to have a full outer shell.

Full outer shell

A full outer shell is known as the noble gas configuration where the outer shell of an atom is energetically stable and contains 8 outer electrons


Inert is a term used to describe an element which will not react as it has a full outer shell of electrons


Group 17: The Halogens


Metalloids, the Semi Metals in the Periodic Table