• Argon is used in light bulbs and fluorescent tubes.light bulb image by Photosani from Fotolia.com
  
  Argon (Ar) is one of the inert gases, along with helium, neon, xenon, krypton and radon. The inert gases can all be found in group 18 of the periodic table, and they are all characterized by very low chemical activity and the absence of odor and color. Argon is no exception; it is not known to form any chemical compounds. This low chemical activity makes it useful for applications that require a dampening of chemical activity.
  
  

Incandescent Light Bulbs and Fluorescent Tubes

• The interior of electric incandescent light bulbs gets its light from a filament that is heated by electric current. In an oxygen-rich or otherwise reactive atmosphere, the heated filament would be consumed by chemical reactions. Filling the bulb with argon eliminates the potential for chemical reactions with the heated filament.
  
  Argon's use in fluorescent tubes is quite different. The argon, mixed with a little mercury, gives off photons when excited by electricity. Simplistically stated, these photons strike the phosphor which coats the glass tube and produce visible light.
  
  

Crystal Growth for Semiconductors

• Argon is used for growing crystals for semiconductors.silicon valley image by .shock from Fotolia.com
  
  Argon's inertness also makes it useful in the semiconductor business. During the production of crystals, heat must be applied to the silicon, germanium or other crystal material and at the same time, the crystals must be grown in a non-reactive atmosphere. Argon gas fills both these roles by blanketing the crystals in an inert gas while conducting heat to them.
  
  

Production of Reactive Elements

• Argon is used as a protective, inert blanket in the production of reactive elements like titanium. In the case of titanium, an atmosphere of argon eliminates the opportunity for the metal to absorb oxygen or nitrogen. Traces of either of these two elements in the finished metal make it brittle. Other reactive elements are similarly isolated by argon during their manufacture.
  
  

Shield Gas for Arc Welding

• Argon is used as shield gas for MIG and TIG arc welding.mig welder image by Jake Hellbach from Fotolia.com
  
  A major use for argon is to provide shield gas for tungsten inert gas (TIG) and metal inert gas (MIG) arc welding. Arc welding involves intense heating of metal by the creation of an electric arc between the target metal and an electrode. This creates a small pool of molten metal, called the welding puddle, around the arc. If the weld puddle is exposed to the atmosphere, the weld becomes contaminated and is weakened. Argon is only one of several inert gases used as a shield gas for TIG and MIG arc welding, but it is an important one.