Krypton, discovery spectrum

Discovery William Ramsay and Morris W. Travers in England discovered xenon in 1898. They extracted krypton from liquid air, and on fractional distillation of this gas they found a new element, heavier than krypton. Its blue glow and characteristic spectrum identified it. It was named xenon, the stranger. 

Eventually they forced themselves to examine the spectrum of the new element. They observed many characteristic lines in the visible wavelength region. A new gas had been discovered. A name. Ramsay asked his thirteen-year-old son for a proposal. He answered promptly novum because it is new. The proposal fell onto fertile ground, but the name was changed to neon, also meaning new but more adapted to the names argon and krypton. The discovery was made in June, 1898. They were satisfied with its atomic weight - the value was 20. 

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