The term 'Noble Gas in Air' refers to ARGON, a chemical element with the symbol Ar and atomic number 18. It is a colorless, odorless, tasteless, non-toxic, inert monatomic gas that makes up 0.934% of the Earth's atmosphere. ARGON is the third most abundant gas in the atmosphere, after nitrogen and oxygen. It is also used in fluorescent lighting and welding, and is an important component of air conditioning systems.