Atmosphere krypton

Krypton is the 81st most abundant element on Earth and ranks seventh in abundance of the gases that make up Earths atmosphere. It ranks just above methane (CH ) in abundance in the atmosphere. Krypton is expensive to produce and thus has hmited use. The gas is captured commercially by fractional distillation of liquid air. Krypton shows up as an impurity in the residue. Along with some other gases, it is removed by filtering through activated charcoal and titanium. 

Boeck, W.L. Meteorological Consequences of Atmospheric Krypton-85." Science, 193, 195-198 (1976). 

Weiss W. H., Sartorius H., and Stockburger H. (1992) The global distribution of atmospheric krypton-85 a data base for the verification of transport and mixing models. 

Kr, a 10-year half-life krypton isotope, is currently released from reprocessing plants to the atmosphere. There will probably be no urgent need in terms of radiation dose to the local population to retain Kr. However, in view of a worldwide accumulation of Kr in the atmosphere, krypton recovery from reprocessing plants is required or will be required in the near future. 

The Group 8A(18) elements are helium (He, the second most abundant element in the universe), neon (Ne), argon (Ar, which makes up about 0.93% of Earth s atmosphere), krypton (Kr), xenon (Xe), and radioactive radon (Rn). Only the last three form compounds [Group 8A(18) Family Portrait]. 

The elements within a group usually have similar properties. For example, the group 8A elements, called the noble gases, are mostly umeactive. The most famihar noble gas is probably helium, used to fill buoyant balloons. Hehum is chemically stable—it does not combine with other elements to form compounds—and is therefore safe to put into balloons. Other noble gases are neon (often used in electronic signs), argon (a small component of our atmosphere), krypton, and xenon. 

Krypton is present in the air to the extent of about 1 ppm. The atmosphere of Mars has been found to contain 0.3 ppm of krypton. Solid krypton is a white crystalline substance with a face-centered cubic structure which is common to all the "rare gases."... 

Del y for Dec y. Nuclear power plants generate radioactive xenon and krypton as products of the fission reactions. Although these products ate trapped inside the fuel elements, portions can leak out into the coolant (through fuel cladding defects) and can be released to the atmosphere with other gases through an air ejector at the main condenser. 

Pure Elements. AH of the hehum-group elements are colorless, odorless, and tasteless gases at ambient temperature and atmospheric pressure. Chemically, they are nearly inert. A few stable chemical compounds are formed by radon, xenon, and krypton, but none has been reported for neon and belium (see Helium GROUP, compounds). The hehum-group elements are monoatomic and are considered to have perfect spherical symmetry. Because of the theoretical interest generated by this atomic simplicity, the physical properties of ah. the hehum-group elements except radon have been weU studied. 

Separation of krypton and xenon from spent fuel rods should afford a source of xenon, technical usage of which is continuously growing (84). As of this writing, however, reprocessing of spent fuel rods is a pohtical problem (see Nuclearreactors). Xenon from fission has a larger fraction of the heavier isotopes than xenon from the atmosphere and this may affect its usefulness in some appHcations. 

Determination in the Atmosphere. Trace amounts of HCl in the atmosphere are detected using krypton homologues as detectors (78),... 

The anomalous micro-composition of the Martian atmosphere with regard to nitrogen, argon, neon, krypton and xenon has also been compared with trapped gases for the Martian meteorite collection (12 in total). The isotope ratios for... 

Bogard D. D. and Garrison D. H. (1998). Relative abundances of argon, krypton, and xenon in the Martian atmosphere as measured in Martian meteorites. Geochimica et Cosmochimica Acta, 62(10) 1829-1835. 

Krypton - the atomic number is 36 and the chemical symbol is Kr. The name derives from the Greek kryptos for concealed or hidden . It was discovered in liquified atmospheric air by the Scottish chemist William Ramsay and the English chemist Morris William Travers in 1898. 

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