Xenon

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Xenon,  54Xe
General properties
Name, symbol Xenon, Xe
Appearance Colorless gas
Exhibits a blue glow when placed in a high voltage electric field
Xenon in the periodic table
Kr

Xe

Rn
IodineXenonCaesium
Atomic number 54
Standard atomic weight (Ar) 131.293(6)
Group, block , p-block
Period period 5
Electron configuration [Kr] 4d10 5s2 5p6
per shell
2, 8, 18, 18, 8
Physical properties
Colorless
Phase Gas
Melting point 161.40 K ​(−111.75 °C, ​−169.15 °F)
Boiling point 165.051 K ​(−108.099 °C, ​​−162.578 °F)
Density at  (0 °C and 101.325 kPa) 5.894 g/L g/L
when liquid, at  2.942 g/cm3 g/cm3 b.p.
Triple point 161.405 K, ​81.77 kPa
Critical point 289.733 K, 5.842 MPa
Heat of fusion 2.27 kJ/mol
Heat of 12.64 kJ/mol
Molar heat capacity 21.01 J/(mol·K)
 pressure
Atomic properties
Oxidation states 0, +1, +2, +4, +6, +8 ​ ​(rarely more than 0; a weakly acidic oxide)
Electronegativity Pauling scale: 2.6
energies 1st: 1170.4 kJ/mol
2nd: 2046.4 kJ/mol
3rd: 3099.4 kJ/mol
Covalent radius 140±9 pm
Van der Waals radius 216 pm
Miscellanea
Crystal structure ​face-centered cubic (fcc)
Speed of sound gas: 169 m/s
liquid: 1090 m/s
Thermal conductivity 5.65×10−3 W/(m·K)
Magnetic ordering Diamagnetic
CAS Registry Number 7440-63-3
Discovery and first isolation William Ramsay and Morris Travers (1898)
· references

Xenon is a chemical element with symbol Xe and atomic number 54. Along with krypton and radon, it is the only noble gas to form true chemical compounds.

Properties

Chemical

Xenon is nonreactive with all chemical compounds, but it can react with fluorine to form xenon fluorides and most notable platinum hexafluoride to form xenon hexafluoroplatinate. Xenon oxides and oxyhalides are also known, and all these are powerful oxidizers and explosives, though they're expensive. Perxenates, XeO4−
6
, are extremely powerful oxidizers capable of oxidizing metals to their highest oxidation state.

Unfortunately, as xenon compounds can only be made with the super dangerous fluorine and fluorine compounds and the relative high price of xenon, their chemistry is not accessible to the amateur chemist.

Physical

Xenon is a dense, colorless, odorless, non-flammable gas. At standard temperature and pressure, pure xenon gas has a density of 5.761 g/cm3, while as a liquid, xenon has a density of up to 3.100 g/mL, with the density maximum occurring at the triple point. Xenon has a relative narrow liquid phase range, boiling at −108.099 °C and melting at −111.75 °C. Only krypton and radon have wider liquid phase range. An interesting property of xenon is its high polarizability due to its large atomic volume, and thus is an excellent solvent. It can dissolve hydrocarbons, biological molecules, and even water.

Availability

Xenon is available as compressed xenon in metal cylinders, and is sold by various compressed gas companies. However, xenon it's an expensive element. Xenon compounds rarely appear for sale at chemical suppliers, limiting our ability to explore the unique chemistry of this element.

Xenon lamps are also a source, though a poor one.

Isolation

Xenon can be isolated from the fractional distillation of air, but this process is too expensive for the amateur chemist to be feasible.

Projects

  • Deep voice
  • Discharge lamps
  • Element collecting
  • Inert atmosphere (though expensive)

Handling

Safety

Being a noble gas, xenon is non-toxic. However, it dissolves in blood and belongs to a select group of substances that penetrate the blood–brain barrier, causing mild to full surgical anesthesia when inhaled in high concentrations, with oxygen. Inhaling large amounts of xenon can lead to asphyxiation, as it displaces the air from lungs.

Xenon compounds are toxic, corrosive and strong oxidizers, as well as explosive. However, the chance of encountering such compounds is very low.

Storage

Xenon cylinders should be placed in cold places, away from any heat and light, preferably in an area above the ground.

Disposal

Xenon can be safely released in air.

References

Relevant Sciencemadness threads