Krypton (Kr), chemical element, a rare gas of Group 18 (noble gases) of the periodic table, which forms relatively few chemical compounds. About three times heavier than air, krypton is colourless, odourless, tasteless, and monatomic. Although traces are present in meteorites and minerals, krypton is more plentiful in Earth’s atmosphere, which contains 1.14 parts per million by volume of krypton. The element was discovered in 1898 by the British chemists Sir William Ramsay and Morris W. Travers in the residue left after a sample of liquid air had boiled almost entirely away.
Krypton is used in certain electric and fluorescent lamps and in a flashlamp employed in high-speed photography. Radioactive krypton-85 is useful for detecting leaks in sealed containers, with the escaping atoms detected by means of their radiation. Krypton is named from the Greek word kryptos, “hidden.” Continue reading from Encyclopedia Britannica
Having discovered the noble gas argon, extracted from air, William Ramsay and Morris William Travers of University College, London, were convinced this must be one of a new group of elements of the periodic table. They decided others were likely to be hidden in the argon and by a process of liquefaction and evaporation they hoped it might leave behind a heavier component, and it did. It yielded krypton in the afternoon of 30th May 1898, and they were able to isolate about 25 cm3 of the new gas. This they immediately tested in a spectrometer, and saw from its atomic spectrum that it was a new element. Continue reading from Royal Society of Chemistry
The discoverers of krypton (Ramsay and Travers) also discovered helium, argon, xenon and neon. Ramsay won the Nobel Prize in chemistry in 1904 for these discoveries. The meter (3.3 feet) was once officially defined by the wavelength of krypton-86, the heaviest stable isotope of krypton. When exposed to an electrical current under low pressure, krypton gas lights up like neon — but instead of red-orange, krypton glows smoky white, according to the Jefferson Lab. Continue reading from LiveScience
