Compared to other elementA substance made of one type of atom only., the noble gasesThe elements in group 0 of the periodic table, named for their lack of chemical reactivity. are inertUnreactive. - they are extremely unreactiveA substance is unreactive or inert if it does not easily take part in chemical reactions. and do not take part in chemical reactions.
Explaining the inertness of noble gases
The table shows the electronic structureA set of numbers to show how the electrons in an atom are arranged in shells, or energy levels. of some noble gases. All the noble gases have complete outer shells:
helium has only two electrons
the other elements have eight electrons in the outer shell
Element
Electronic structure
Helium
2
Neon
2.8
Argon
2.8.8
Element
Helium
Electronic structure
2
Element
Neon
Electronic structure
2.8
Element
Argon
Electronic structure
2.8.8
When elements react, their atomThe smallest part of an element that can exist. complete their outer shells by losing, gaining, or sharing electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons.. Atoms of group 0 elements already have stable arrangements of electrons. This means that they have no tendency to lose, gain, or share electrons. This is why the noble gases are unreactive. It also explains why atoms of group 0 elements do not share electrons to form molecules.