Periodic  Table of the Elements
  << BACK | PERIODIC TABLE | ALPHABETICAL LIST >>Info & DownloadsADDITIONAL INFO
ARGON
Download pdf Book
to Elements Alphabetical Listing
Atomic Number:18
Atomic Symbol:Ar
Atomic Weight:39.948
Electron Configuration:[Ne]3s23p6
Total Isotopes25
Total Isomers1
Radioactive Isotopes21
Stable Isotopes3
X-Ray Energies
2.96
3.19
LL0.22
Mz

 View Nuclear Periodic Table 
 View Isotopic & Isomeric Data 


Spectra of Gas Discharges
Spectra of Gas Discharges

History

(Gr. argos, inactive) Its presence in air was suspected by Cavendish in 1785, discovered by Lord Rayleigh and Sir William Ramsay in 1894.

Sources

Element DisplaysThe gas is prepared by fractionation of liquid air because the atmosphere contains 0.94% argon. The atmosphere of Mars contains 1.6% of 40Ar and 5 p.p.m. of 36Ar.
Properties

Argon is two and one half times as soluble in water as nitrogen, having about the same solubility as oxygen. Argon is colorless and odorless, both as a gas and liquid. Argon is considered to be a very inert gas and is not known to form true chemical compounds, as do krypton, xenon, and radon.

Isotopes

Naturally occurring argon is a mixture of three isotopes. Twelve other radioactive isotopes are known to exist.

Uses

It is used in electric light bulbs and in fluorescent tubes at a pressure of about 400 Pa. and in filling photo tubes, glow tubes, etc. Argon is also used as an inert gas shield for arc welding and cutting, as blanket for the production of titanium and other reactive elements, and as a protective atmosphere for growing silicon and germanium crystals.

Sources: Los Alamos National Laboratory; CRC Handbook of Chemistry and Physics; American Chemical Society
Element image from www.element-collection.com used with permission
      « BACK | PERIODIC TABLE | ALPHABETICAL LIST | HOME »Top of Page
Join Today!
.:: Radiochemistry.org© - 2003 ::.