Krypton was discovered in Britain in 1878 by Sir William Ramsay, a Scottish chemist, and Morris Travers, an English chemist, in residue
left from evaporating nearly all components of liquid air. Neon was discovered by a similar procedure by the
same workers just a few weeks later.[3]
William Ramsay was awarded the 1904 Nobel Prize in Chemistry for discovery of a
series of noble
gases, including krypton.
In 1970, an international agreement defined the meter in terms of wavelength of light emitted by the krypton-86
isotope (wavelength of 605.78 nanometers). This agreement replaced the
longstanding standard meter located in Paris, which was a metal bar made of a platinum-iridium alloy (the bar was originally estimated
to be one ten-millionth of a quadrant of the Earth's polar circumference), and was itself
replaced by a definition based on the speed of light — a fundamental physical
constant. However, in 1927, the International Conference on Weights and Measures
had redefined the meter in terms of a red cadmium spectral line (1 m =
1,553,164.13 wavelengths).[4] In
October 1983, the same bureau defined the meter as the distance that light
travels in a vacuum during 1/299,792,458 s
left from evaporating nearly all components of liquid air. Neon was discovered by a similar procedure by the
same workers just a few weeks later.[3]
William Ramsay was awarded the 1904 Nobel Prize in Chemistry for discovery of a
series of noble
gases, including krypton.
In 1970, an international agreement defined the meter in terms of wavelength of light emitted by the krypton-86
isotope (wavelength of 605.78 nanometers). This agreement replaced the
longstanding standard meter located in Paris, which was a metal bar made of a platinum-iridium alloy (the bar was originally estimated
to be one ten-millionth of a quadrant of the Earth's polar circumference), and was itself
replaced by a definition based on the speed of light — a fundamental physical
constant. However, in 1927, the International Conference on Weights and Measures
had redefined the meter in terms of a red cadmium spectral line (1 m =
1,553,164.13 wavelengths).[4] In
October 1983, the same bureau defined the meter as the distance that light
travels in a vacuum during 1/299,792,458 s