Niton, later known as radon, was the last noble gas to be discovered. In , Ramsay was awarded the Nobel Prize in Chemistry for his research of noble gases. The noble gases were formerly known as the rare gases or the inert gases. It was later shown that some were quite common and that some were not completely unreactive. In , Neil Bartlett created xenon platinum hexafluoride, the first chemical compound of a noble gas.
Compounds of radon were created in the same year and compounds of krypton in No longer thought of as rare or inert, these elements came to be known as the noble gases. Like the so-called noble metals gold, silver, platinum, etc. Krypton played an important role in science from , when the length of the meter was defined as 1,, The meter was later defined in terms of the speed of light in a vacuum, but krypton continues to be used in scientific research.
In order to separate krypton, as well as the other gases, from the liquid air, the air is slowly warmed in a process called fractional distillation. Operating under the assumption that each liquid has its own distinct temperature at which it changes to a gas, fractional distillation separates the gases within air one at a time. Although traces of krypton are found in various minerals, the most important source of krypton is Earth's atmosphere.
Air is also the most important source for the other noble gases, with the exception of helium obtained from natural gas and radon obtained as a byproduct of the decay of radioactive elements. At sea level, dry air contains It also contains 0. Other components of dry air include carbon dioxide, hydrogen, methane, nitric oxide, and ozone.
Krypton can also be obtained from the fission of uranium, which occurs in nuclear power plants. Unlike air, which contains only the stable isotopes of krypton, this process produces both stable isotopes and radioactive isotopes of krypton. The most important factor in the quality control of krypton production is ensuring that the final product contains only krypton.
The process of fraction distillation has been developed to the point where it produces very pure products from air, including krypton. Random samples of krypton are tested for purity by spectroscopic analysis. This process involves heating a substance until it emits light. The light then passes through a prism or a grating in order to produce a spectrum, in the same way that sunlight produces a rainbow.
Spectroscopic analysis is particularly well suited to studying gases, because heated gases tend to produce sharp, bright lines on a spectrum of pure krypton, it is possible to tell if any impurities are present.
For those that are curious, pictures of krypton gas and krypton plasma can be found in the Questions and Answers section of this site. Estimated Oceanic Abundance : 2. Number of Stable Isotopes : 5 View all isotope data.
Electron Shell Configuration :. Krypton Previous Isotopes Next. They boiled a sample of liquefied air until they got rid of the water, oxygen, nitrogen, helium and argon. It produced a spectrum with bright yellow and green lines. Because they had suspected its presence, but had to look for it by removing all that other stuff, Ramsay and Travers gave the element with atomic number 36 the name krypton, from the Greek kryptos for hidden think cryptography or encryption.
Within weeks, the scientifically dynamic duo had detected a duet of other noble gases: neon and xenon. Ramsay was already responsible for discovering helium with Lord Rayleigh in and argon in , giving him ownership of nearly an entire column of the periodic table.
The purpose, other than winning world records, is to advance research on nuclear fusion. Krypton has other scientific superpowers as well.
Radioactive isotopes of krypton — versions of the atom with differing numbers of neutrons in their nuclei — are produced naturally when cosmic rays from space hit krypton atoms in the atmosphere, said Christo Buizert, a postdoctoral researcher in geology and geophysics at Oregon State University.
These radioactive isotopes are unstable, meaning they decay over time. This timed decay creates an atomic "clock," not unlike carbon, a radioactive element with a half-life of about 5, years. Carbon is great for dating organic objects that date back tens of thousands of years, but many elements of the Earth are far older, Buizert said.
He and his colleagues have used a krypton isotope, krypton, with a half-life of , years to date ice cores in the Antarctic back to , years old. The oldest Antarctic ice ever found fell as snow , years ago. Bubbles in the ice trap atmospheric gases as they were when the snow fell, Buizert told Live Science. By measuring the levels of krypton and comparing them to the current atmosphere, researchers can use the known rate of decay of the isotope to determine the ice's age.
The krypton measurement technique is only about a decade old, Buizert said.
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