Argon is a colourless, odourless, gaseous element found in the air and volcanic gases, and is used especially as a filler for electric bulbs and electron tubes. It has the symbolAr.
Argon was found to exist in the atmosphere in small quantity (about 1 per cent of the whole), its discovery being due to Lord Rayleigh and Professor Ramsay in 1894. Its discovery was led up to by the fact that the density of nitrogen as derived from the atmosphere differs from its density as derived from other sources, and this difference was found to be due to the presence of argon, which is about half as heavy again as nitrogen. The new substance was named argon by its discoverers on account of its chemical inertness (from Greek a, not, ergon work), that is, its refusal to form compounds by combining with other substances. Ramsay since showed that this 'argon' consists of a mixture of five hitherto unknown gaseous elements termed helium, neon, argon, krypton, and xenon - now called the noble gases. The amounts are extremely small; thus by volume 0.937 of argon per 100, 1 or 2 of neon per 1000,1 or 2 of helium per 1,000,000; similarly for krypton and xenon, 1 per 20 million. At the time of their discovery they were considered to be of no general importance. Research Argon
Abbreviations
SciTech
Research Argon