Element History

The Scottish chemist Sir William Ramsay and his British student Morris Travers discovered krypton on May 30, 1898. It was found after evaporating almost all components of liquid air. Ramsay later discovered xenon and neon in the same way. The word krypton comes from the Greek word "kryptos", meaning hidden, referencing the way krypton is obtained. In 1960, the length of the meter was defined in terms of the spectral line of krypton-86, one of krypton's 15 isotopes. It was determined that a meter is equal to 1,650,763.73 wavelengths of krypton-86's spectral line.

Physical and Chemical Properties

Krypton is a colorless, odorless gas in its natural state and is mostly unreactive, since it is one of the noble (or inert) gases. However, although krypton was originally believed to be completely inert, this has been proven wrong. Krypton forms a few compounds, most notable krypton difluoride, or KrF2. Krypton is characterized by its green and orange spectral lines. In its solid state, krypton is a white crystalline. It boils at an extremely low temperature of -152.9˚ C and melts at -157.39˚ C. Krypton is 2.8 times denser than air, with a density of 3.749 grams/Liter. Krypton's atomic number is 36 and it has an atomic mass of 83.80. Krypton has a complete outer shell of eight valence electrons, like all other noble gases.

Obtaining Krypton

Krypton is obtained by allowing water, argon, oxygen, helium and nitrogen to evaporate from liquid air. It makes up around 0.0001% of the Earth's atmosphere, and is found in trace amounts in the Earth's crust. The atmosphere of Mars has also been found to contain krypton. Krypton is always found in a gaseous form, and can be found in nature inside volcanoes, geysers and hot springs.

Element Uses

Krypton is not used commonly, because it is difficult and very expensive to obtain. However, krypton is used in fluorescent lamps, often with argon. It is also used in high-speed photographic flashes and lightning airfields because it has an extremely fast response to electric currents and can penetrate fog and haze easily. Krypton is also used with phosphorus to produce materials that glow in the dark. Krypton is occasionally used with other gases to produce a luminous, glowing light, like its "cousin", neon.

Bibliography

Krypton History, Properties, Ways to Obtain, and Uses:
Gagnon, Steve. "The Element Krypton." Jefferson Lab. Web. 07 Dec. 2011. http://education.jlab.org/itselemental/ele036.html

"Krypton." Carondelet High School. Web. 07 Dec. 2011.

"Krypton." The Third Millennium Online! Web. 07 Dec. 2011.

"Krypton (Kr) - Chemical Properties, Health and Environmental Effects." Water Treatment and Purification - Lenntech. Web. 07 Dec. 2011. .

Winter, Mark. "Krypton Historical Information." WebElements Periodic Table of the Elements. The University of Sheffield. Web. 07 Dec. 2011.

Images:
Plasma Globe: Dunn, Mark. "TeslaBoys Plasma Globe Projects." TeslaBoys Tesla and Plasma Experiments, Tesla Coils, Plasma Ball, Plasma Globe, Jacob's Ladder. Web. 07 Dec. 2011.

Krypton. Photograph. PeriodicTable.com. Web. .