Argon: abundance, 8 discovery

Soon after hearing of the discovery of argon, Lecoq de Boisbaudran predicted that it might belong to a family of absolutely inert elements all of which were then unknown, and that their atomic weights would be 20.0945, 36.40 0.08, 84.01 0.20, and 132.71 0.15. He also predicted that the first two of these elements would be more abundant than the others (33, 34). 

Argon is an important element for nucleosynthesis, for the discovery and interpretation of isotopic anomalies, and for the interpretation of the origin of planetary atmospheres. Argon is the eleventh most abundant element in the universe thus it is an important datum for nucleosynthesis theories. It is much rarer in terrestrial abundances because most Ar was lostinto space (owing to its inertness and high volatility) as the Earth formed. 

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