Krypton is a chemical element that is a colorless, odorless, tasteless noble gas that occurs in trace amounts in the Earth's atmosphere.

Emissions

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Krypton emission spectrum for 400 nm - 700 nm. Credit: McZusatz.{{free media}}

Plasmas

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Vial contains glowing ultrapure krypton. Credit: Jurii.{{free media}}

Glass tubes, with a wire wound over each directs the plasma flow.

Gases

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Spectrum = gas discharge tube: the noble gas: krypton Kr. Used with 1,8kV, 18mA, 35kHz. ≈8" length. Credit: Alchemist-hp.{{free media}}

Krypton is a noble gas.

Liquids

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Liquid krypton is used to construct quasi-homogeneous electromagnetic calorimeters, for example, the calorimeter of the NA48 experiment at CERN containing about 27 tonnes of liquid krypton.

Solids

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Solid krypton is white and has a face-centered cubic crystal structure, which is a common property of all noble gases (except helium, which has a hexagonal close-packed crystal structure).

Isotopes

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Krypton has 5 stable isotopes (80, 82, 83, 84, 86).

Naturally occurring krypton in Earth's atmosphere is composed of five stable isotopes, plus one isotope (78Kr) with such a long half-life (9.2×1021 years) that it can be considered stable. (This isotope has the second-longest known half-life among all isotopes for which decay has been observed; it undergoes double electron capture to 78Se).[1][2] In addition, about thirty unstable isotopes and nuclear isomers are known.[3] Traces of 81Kr, a cosmogenic nuclide produced by the cosmic ray irradiation of 80Kr, also occur in nature: this isotope is radioactive with a half-life of 230,000 years. Krypton is highly volatile and does not stay in solution in near-surface water, but 81Kr has been used for radiometric dating old (50,000–800,000 years) groundwater.[4]

Atmospheres

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Krypton-85 (85Kr) is an inert radioactive noble gas with a half-life of 10.76 years, produced by the nuclear fission of uranium and plutonium, such as in nuclear bomb testing and nuclear reactors. 85Kr is released during the reprocessing of fuel rods from nuclear reactors. Concentrations at the North Pole are 30% higher than at the South Pole due to convective mixing.[5]

Resources

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See also

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References

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  1. Patrignani, C.; et al. (Particle Data Group) (2016). "Review of Particle Physics". Chinese Physics C. 40 (10): 100001. Bibcode:2016ChPhC..40j0001P. doi:10.1088/1674-1137/40/10/100001
  2. Gavrilyuk, Yu. M.; Gangapshev, A. M.; Kazalov, V. V.; Kuzminov, V. V.; Panasenko, S. I.; Ratkevich, S. S. (4 March 2013). "Indications of 2ν2K capture in 78Kr". Phys. Rev. C 87 (3): 035501. doi:10.1103/PhysRevC.87.035501. 
  3. Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
  4. Thonnard, Norbert; MeKay, Larry D.; Labotka, Theodore C. (2001-02-05). "Development of Laser-Based Resonance Ionization Techniques for 81-Kr and 85-Kr Measurements in the Geosciences" (PDF). University of Tennessee, Institute for Rare Isotope Measurements. pp. 4–7. Retrieved 2007-03-20.
  5. "Resources on Isotopes". U.S. Geological Survey. Retrieved 2007-03-20. {{cite web}}: |archive-date= requires |archive-url= (help)