| LC control no. | sh 85053403 |
|---|---|
| Topical heading | Gases, Rare |
| Variant(s) | Elements, Inert Gases, Inert Gases, Noble Inert elements Inert gases Noble gases Rare gases |
| See also | Nonmetals |
| Found in | Wikipedia, Oct. 25, 2012 (under Inert: In chemistry, the term inert is used to describe a substance that is not chemically reactive. The noble gases were previously known as inert gases because of their perceived lack of participation in any chemical reactions. The reason for this is that their outmost electron shells (valence shells) are completely filled, so that they have little tendency to acquire or lose electrons. It is now known that these gases in fact do react to form chemical compounds, such as xenon tetrafluoride. Hence, they have been renamed to noble gases; under Noble gas: The noble gases make a group of chemical elements with similar properties: under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn). For the first six periods of the periodic table, the noble gases are exactly the members of group 18 of the periodic table. However, it is possible that due to relativistic effects, the group 14 element flerovium exhibits some noble-gas-like properties, instead of the group 18 element ununoctium) |
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