Argon

Argon is a chemical element with the symbol Ar and atomic number 18. It is a colorless, odorless, and inert gas that is part of the noble gases group in the periodic table. Argon constitutes about 0.93% of the Earth's atmosphere by volume and is the third most abundant gas in the atmosphere after nitrogen and oxygen. Due to its chemical inertness, argon does not readily react with other elements or compounds, which makes it useful in various applications, such as providing an inert atmosphere for welding and other industrial processes. Argon is also commonly used in light bulbs and for the preservation of historical documents and artifacts due to its non-reactive properties. Its name is derived from the Greek word "argon," meaning "inactive" or "lazy," reflecting its lack of chemical reactivity.