Noble gases are also called inert gases.
Noble gases are present in the group 18th of the periodic table and are non reactive because their outermost shell is complete and has a very stable electronic configuration. Noble gases do not accept or remove electron that’s why noble gases do not react with any other atom.
Example;
The first element of group 18th is helium(He) have 2 electrons in it’s outermost shell and is stable and non reactive.
Neon(Ne) has 10 electrons i.e,
2 electrons in inner shell and 8 electrons in the second or outermost shell.
Why noble gases are non reactive?
