Noble gas

Noble Gases or rare gases are very stable, nearly chemically inert elements, that are in a gaseous state at room temperature. A Noble Gas is a gas that's outer shell is full. All of the outer electron shells of the Noble Gases are filled with 8 electrons except for Helium which has only 2 in the first shell. The Noble Gases were discovered in 1886. Originally they were called inert gases because people thought that they were nonreactive. That has since been proven wrong. In 1962 the British chemist Neil Bartlett synthesised the first group 0 compound, xenon hexafluoroplatinate. Since then, chemists have been able to create compounds with three of the Noble Gases (xenon, krypton, and radon). The electron configurations of the Noble Gases are very stable and usually very resistant to any change.

The Six Noble Gases

 * 1) Helium has an atomic number of 2, the Atomic symbol is He, and the atomic mass is 4.002602g/mol.  The name helium comes from Helios which means sun in Greek.  It was first discovered by Sir William Ramsay in 1895.
 * 2) Neon has an atomic number of 10, the Atomic Symbol Ne, and the atomic mass of 20.180g/mol. Its name comes from the greek word Neos which means new.  It was discovered by Sir William Ramsay in 1898
 * 3) Argon has an Atomic Number of 18, the Atomic Symbol Ar, and the Atomic Mass of 39.948g/mol.  The name comes from the Greek word Argon which means inactive.  It was discovered by Sir William Ramsay in 1894.
 * 4) Krypton has an Atomic Number of 36, the Atomic Symbol Kr, and the Atomic Mass of 83.80g/mol.  Its name comes from the Greek word kryptos which means hidden.  It was discovered in 1898 by Sir William Ramsay.
 * 5) Xenon has an Atomic Number of 54, the Atomic Symbol Xe, and the Atomic Mass of 131.290g/mol.  The word Xenon comes from the Greek word xenon which means stranger it was discovered by Sir William Ramsay in 1898.
 * 6) Radon has an Atomic Number of 86, the Atomic Symbol Rn, and the Atomic Mass of 222.018g/mol.  The name comes from the word radium and it was discovered in 1898 by Fredrich Ernst Dorn.*



Uses of Noble Gases
Even though Noble Gases usually do not combine with other elements they have many different uses. Have you ever seen the signs with neon lights that flash and say words on them? Those signs are made using neon and argon. Helium is used for balloons, blimps, and airships because it is lighter than air so they will float, and is less flammable than hydrogen. Krypton is used for lighting, Xenon is used in powerful lamps and bubble chambers. Radon is used for the treatment of cancer. 

Related References

 * Noble gas Wikipedia
 * Noble GasesChemical Elements

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