Symbol: Ar

Atomic Number: 18

Atomic Weight: 39.948

Argon (Ar, atomic number 18) is the third most common gas in the world, even more so than carbon dioxide. The word "argon" means inactive, inert in Greek and refers to this gas in that it reacts with very few other elements in the periodic table. It has eight electrons in the outer shell, which make it very stable and resistant to reactions.

Argon is an odorless and colorless gas, found in the atmosphere to a small extent. It does not form chemical compounds and is heavier than air.

Argon was isolated by Sir William Ramsay and Lord Rayleigh in...Read More