The noble gases, also known as the inert gases and aerogens, are the elements that belong to group 18 of the modern periodic table. The elements that belong to this group are: 1. Helium (He) 2. Neon (Ne) 3. Argon (Ar) 4. Krypton (Kr) 5. Xenon (Xe) 6. Radon (Rn) They are known to possess extremely low chemical reactivity (hence the name inert gas). This is because all the noble gases have stable electronic configurations. This is the reason why noble gases do not form molecules easily and are mostly found as mono-atomic gases.