(Gr. kryptos, hidden) Discovered in 1898 by Ramsay and Travers. Krypton present in the air at about 1ppm (one part per million parts). The atmosphere of Mars has been found to contain small amounts of krypton.
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inert gas, only known compounds are with fluorine, colorless, odorless, fairly expensive
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spectral line used for international measurement of a meter, chemical analysis, filling gas for fluorescent lights, high speed photography flash lamps