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Inorganic Chemistry

Noble Gases

Definition and meaning of Noble Gases in chemistry.

Noble gases are a group of chemical elements located in Group 18 of the periodic table characterized by their extremely low chemical reactivity and full valence electron shells. They are colorless, odorless, nonflammable, monatomic gases at room temperature.

In more detail

The noble gases include helium, neon, argon, krypton, xenon, and radon, along with the synthetic element oganesson. Because their outermost electron shells are completely filled, they are highly stable and rarely form chemical compounds under standard laboratory conditions. While they were historically thought to be completely inert, modern chemists have successfully synthesized a few unique compounds containing heavier noble gases like xenon and krypton under extreme temperatures and pressures.

Key facts

FieldInorganic Chemistry
ElementsHe, Ne, Ar, Kr, Xe, Rn, Og
Valence Electrons8 (except Helium, which has 2)
Example

Argon is frequently used as an inert shielding gas in arc welding to prevent the extremely hot metal from reacting with oxygen or nitrogen in the ambient air.

Frequently asked questions

Why are noble gases so unreactive?

They have a complete valence electron shell, which represents a very stable, low-energy electron configuration.

Can noble gases form compounds?

Yes, under specific conditions with highly electronegative elements like fluorine, heavier noble gases like xenon can form compounds such as XeF4.