Like xenon, krypton is highly volatile when it is near surface waters and 81Kr has therefore been used for dating old (50,000 - 800,000 year) groundwater. It is radioactive with a half-life of 250,000 years. 81Kr is the product of atmospheric reactions with the other naturally occurring isotopes of krypton. Krypton's spectral signature is easily produced with some very sharp lines. Naturally occurring krypton is made of five stable and one slightly radioactive isotope. See in its paragraph starting " Many recent findings". ArKr+ and Kr H+ molecule- ions have been investigated and there is evidence for Kr Xe or KrXe+.Īt the University of Helsinki in Finland, HKrCN and HKrCCH (krypton hydride-cyanide and hydrokryptoacetylene) were synthesized and determined to be stable up to 40 K(M. Other fluorides and a salt of a krypton oxoacid have also been found. Following the first successful synthesis of xenon compounds in 1962, synthesis of krypton di fluoride was reported in 1963. Like the other noble gases, krypton is widely considered to be chemically inert. It can be extracted from liquid air by fractional distillation. The concentration of krypton in earth's atmosphere is about 1 ppm. In October 1983 the Bureau International des Poids et Mesures (International Bureau of Weights and Measures) defined the metre as the distance that light travels in a vacuum during 1/299,792,458 s. But only 23 years later, the Krypton-based standard was replaced itself by the speed of light-the most reliable constant in the universe. This agreement replaced the longstanding standard metre 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). In 1960 an international agreement defined the metre in terms of light emitted from a krypton isotope. Krypton ( Greek κρυπτός meaning "hidden") was discovered in Great Britain, 1898 by Sir William Ramsay and Morris Travers in residue left from evaporating nearly all components of liquid air. Solidified krypton is white and crystalline with a face-centered cubic crystal structure which is a common property of all "rare gases". It is one of the products of uranium fission. Krypton, a noble gas due to its very low chemical reactivity, is characterized by a brilliant green and orange spectral signature.
Image of a krypton filled discharge tube shaped like the element's atomic symbol. Krypton can also form clathrates with water when atoms of it are trapped in a lattice of the water molecules. Krypton is inert for most practical purposes but it is known to form compounds with fluorine. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere, is isolated by fractionating liquefied air, and is often used with other rare gases in fluorescent lamps. Kr- 85 is also used to detect leaks in containers.Krypton ( IPA: /ˈkrɪptən/ or /ˈkrɪptan/) is a chemical element with the symbol Kr and atomic number 36.The isotope krypton- 85 is used along with phosphorus to produce objects that shine in dark.Krypton- 83 is used in Magnetic Resonance Imaging because of its high spin.The most abundant one is krypton- 84 with 57 percentage. There are six, stable naturally occurring isotopes. There occur almost 25 isotopes of krypton from mass number 71 to 95. Krypton fluorides are used in some lasers.Krypton ion laser is used in the research and the study of proteins.From 1960 to 1983, the wavelength of krypton- 86 was used as a standard unit of length.It is also used along with other gases in neon signs to produce brilliant green light.It is used in arc lights such as in airports.High-speed photography and some high-quality photographic flashes use krypton.Mixtures of argon and krypton are used in light bulbs.Krypton is used in lightening products such as bulbs, lamps, projection lamps, and fluorescent tubes.Due to the highly expensive process of obtaining krypton from air, its practical applications are limited but some important uses are given below:.
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