Noble gases (formally referred to as inert or rare gases) make up Group 18 of the periodic table of the elements. The term "noble" refers to their low reactivity with other elements to form compounds. It was borrowed from the phrase "noble metals," used to describe metals resistant to corrosion and oxidation, such as palladium, silver, gold and platinum.
The Noble Gases
The noble gases consist of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn).
Properties of Noble Gases
In addition to low reactivity, noble gases exhibit low melting and boiling points and exist in a monoatomic (one-atom) state. All isotopes of radon are radioactive with relatively short half-lives. Although the noble gases have low reactivity, it does not mean they are unreactive. For this reason, the previously used term "inert" is inappropriate.
Abundance of Noble Gases
Helium is one of the most abundant elements in the universe. On Earth, argon comprises 0.0934% of air by volume. Due to the prevalence of these gases on Earth and throughout the universe, the previously used term "rare gases" is also inappropriate.
Source of Noble Gases
Neon, argon, and krypton, xenon are procured from the air by fractional distillation. Helium is commercially produced from natural gas wells.
Uses of Noble Gases
Due to their low reactivity, noble gases are often employed to prevent corrosion. Helium is mixed in diver’s air supplies at depth. The noble gases are also employed in light fixtures.