Encyclopedia > Xenon

  Article Content

Xenon

General
Name, Symbol, NumberXenon, Xe, 54
Chemical series Noble gases
Group, Period, Block18 (VIIIA), 5, p
Density, Hardness 5.9 kg/m3(273 K), NA
Appearance colorless
Atomic Properties
Atomic weight 131.293 amu
Atomic radius (calc.) no data (108) pm
Covalent radius 130 pm
van der Waals radius 216 pm
Electron configuration [Kr]4d10 5s2 5p6
e- 's per energy level2, 8, 18, 18, 8
Oxidation states (Oxide) 0 (weak acid)
Crystal structure Cubic face centered
Physical Properties
State of matter gas (nonmagnetic)
Melting point 161.4 K (-169.1 °F)
Boiling point 165.1 K (-162 °F)
Molar volume 35.92 ×10-3 m3/mol
Heat of vaporization 12.636 kJ/mol
Heat of fusion 2.297 kJ/mol
Vapor pressure NA
Speed of sound 1090 m/s at 293.15 K
Miscellaneous
Electronegativity 2.6 (Pauling scale)
Specific heat capacity 158 J/(kg*K)
Electrical conductivity no data
Thermal conductivity 0.00569 W/(m*K)
1st ionization potential 1170.4 kJ/mol
2nd ionization potential 2046.4 kJ/mol
3rd ionization potential 3099.4 kJ/mol
Most Stable Isotopes
isoNAhalf-life DMDEDP
124Xe0.1%Xe is stable with 70 neutrons
126Xe0.09%Xe is stable with 72 neutrons
128Xe1.91%Xe is stable with 74 neutrons
129Xe26.4%Xe is stable with 75 neutrons
130Xe4.1%Xe is stable with 76 neutrons
131Xe21.29%Xe is stable with 77 neutrons
132Xe26.9%Xe is stable with 78 neutrons
134Xe10.4%Xe is stable with 80 neutrons
136Xe8.9%2.36 E21 yBeta-no data136Ba
SI units & STP are used except where noted.
Xenon is a chemical element in the periodic table that has the symbol Xe and atomic number 54. A colorless, very heavy, odorless noble gas, xenon occurs in the earth's atmosphere in trace amounts and was part of the first noble-gas compound synthesized.

Table of contents

Notable Characteristics Xenon is a member of the zero valance elements that are called noble or inert gases. The word "inert" is no longer used to describe this chemical series since some zero valence elements do form compounds. In a vacuum tube xenon emits a beautiful blue glow when the gas is excited by electrical discharge. Using several hundred kilobars of pressure metallic xenon has been made. Applications This gas is most widely and most famously used in light-emitting devices such as bactericidal[?] lamps, electron tubes, stroboscopic lamps and photo flash units, and lamps that are used to excite ruby lasers that then generate coherent light[?]. Other uses;

History Xenon (Greek xenon meaning "stranger") was discovered by William Ramsay and Morris Travers[?] in 1898 in the residue left over from evaporating components of liquid air. Occurrence It is a trace gas in Earth's atmosphere, occurring in one part in twenty million. The element is obtained commercially through extraction from the residues of liquefied air. This noble gas is naturally found in gases emitted from some mineral springs[?]. Xe-133 and Xe-135 are synthesized by neutron irradiation within air-cooled nuclear reactors. Compounds Before 1962, xenon and the other noble gases gases were generally considered to be chemically inert and not able to form compounds. Evidence since this time has been mounting that xenon, along with other noble gases, do in fact form compounds. Some of the xenon compounds are; difluoride, hexafluoride, sodium perxenate, tetrafluoride, xenon deuterate, xenon hydrate. The highly explosive compound xenon trioxide has also been made. There are at least 80 xenon compounds in which fluorine or oxygen are bonded to xenon. Some compounds of xenon are colored but most are colorless. Isotopes Naturally occurring xenon is made of eight stable and one slightly radioactive isotopes. Beyond these stable forms, there are 20 unstable isotopes that have been studied. Xe-129 is produced by beta decay of I-129 (half-life: 16 million years); Xe-131, Xe-132, Xe-134 and Xe-136 are fission products of both U-238 and Pu-244. Because Xe is a tracer for two parent isotopes, Xe isotope ratios in meteorites are a powerful tool for studying the formation of the solar system[?]. The I-Xe method of dating gives the time elapsed between nucleosynthesis and the condensation of a solid object from the solar nebula. Xenon isotopes are also a powerful tool for understanding terrestrial differentiation. Excess Xe-129 found in carbon dioxide well gases from New Mexico was believed to be from the decay of mantle-derived gases soon after Earth's formation. Precautions The gas can be safely kept in normal sealed glass containers at standard temperature and pressure. Xenon non-toxic, but many of its compounds are highly toxic due to their strong oxidation properties.

External links



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Charles V, Holy Roman Emperor

... Holy Roman Emperor - Wikipedia <<Up     Contents Charles V, Holy Roman Emperor Charles (Ghent February 25, 1500-San Jerónimo de Yuste[?], ...

 
 
 
This page was created in 39.4 ms