Inert gas

Gas which does not chemically react under the specified conditions

An inert gas is a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds. Though inert gases have a variety of applications, they are generally used to prevent unwanted chemical reactions with the oxygen (oxidation) and moisture (hydrolysis) in the air from degrading a sample. Generally, all noble gases except oganesson, nitrogen, and carbon dioxide are considered inert gases. The term inert gas is context-dependent because several of the noble gases, including nitrogen and carbon dioxide, can be made to react under certain conditions.

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