Ar Argon Index

Atomic Mass 39.948 Atomic Number 18 Name Origins Greek, argos = "inactive." Year Discovered 1894 Discovery Credits Discovered by Lord Rayleigh (London) and Sir William Ramsay (Bristol), UK Remarks Colorless, odorless gas comprising 1 percent of the atmosphere. Used as inert atmosphere in lamps and high temperature metallurgy. Found in potassium-bearing minerals as a trapped gas due to the radioactive decay of K⁴⁰ References Emsley, J., 1991; THE ELEMENTS : Sec. Ed., Clarendon Press, Oxford, 251 p. See Also WebElements, ChemiCool