Xenon

Xenon is a non-metal chemical element. It has the chemical symbol Xe and atomic number 54. It is one of the few elements that are a gas at the standard temperature and pressure.

Xenon, ₀₀Xe

A xenon-filled discharge tube glowing light blue
Xenon
Pronunciation	/ˈzɛnɒn/[1] (ZEN-on) /ˈziːnɒn/[2] (ZEE-non)
Appearance	colorless gas, exhibiting a blue glow when placed in an electric field
Standard atomic weight Ar°(Xe)
	131.293(6)[3]
Abundance
in the Earth's crust	2 × 10-9%
in the solar system	1.56 × 10-8%
Xenon in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Kr ↑ Xe ↓ Rn iodine ← xenon → caesium
Group	group 18 (noble gases)
Period	period 5
Block	p-block
Electron configuration	[Kr] 4d10 5s2 5p6
Electrons per shell	2, 8, 18, 18, 8
Physical properties
Phase at STP	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 STP)	5.894 g/L
when liquid (at b.p.)	2.942 g/cm3[4]
Triple point	161.405 K, ​81.77 kPa[5]
Critical point	289.733 K, 5.842 MPa[5]
Heat of fusion	2.27 kJ/mol
Heat of vaporization	12.64 kJ/mol
Molar heat capacity	21.01[6] J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 83 92 103 117 137 165
Atomic properties
Oxidation states	0, +2, +4, +6, +8 (rarely more than 0; a weakly acidic oxide)
Electronegativity	Pauling scale: 2.6
Ionization 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
Spectral lines of xenon
Other properties
Natural occurrence	primordial
Crystal structure	​face-centered cubic (fcc)
Speed of sound	gas: 178 m·s−1 liquid: 1090 m/s
Thermal conductivity	5.65×10−3 W/(m⋅K)
Magnetic ordering	diamagnetic[7]
Molar magnetic susceptibility	−43.9×10−6 cm3/mol (298 K)[8]
CAS Number	7440-63-3
History
Discovery and first isolation	William Ramsay and Morris Travers (1898)
Isotopes of xenon v e
Main isotopes[9] Decay abun­dance half-life (t1/2) mode pro­duct 124Xe 0.095% 1.8×1022 y[10] εε 124Te 125Xe synth 16.9 h ε 125I 126Xe 0.0890% stable 127Xe synth 36.345 d ε 127I 128Xe 1.91% stable 129Xe 26.4% stable 130Xe 4.07% stable 131Xe 21.2% stable 132Xe 26.9% stable 133Xe synth 5.247 d β− 133Cs 134Xe 10.4% stable 135Xe synth 9.14 h β− 135Cs 136Xe 8.86% 2.165×1021 y[11][12] β−β− 136Ba
Category: Xenon view talk edit | references

History

Sir William Ramsay and M. W. Travers discovered this element in 1898. The element's name came from the Greek word xenos, which means 'stranger'.

Chemistry

Xenon belongs to the group of the noble gases. Noble gases are very unreactive. However, in 1962, chemists have found that xenon can react with fluorine under special conditions, such as high pressure and high temperature. It is not known why xenon behaves differently under these circumstances. There are also some compounds with oxygen. The gas is not very reactive, because if fulfills the octet rule. This means that a lot of energy is needed to remove an electron from xenon. This activation energy for xenon is 1172 kJ/mol. To remove a second electron from xenon, an energy of 2046.4 kJ/mol is needed.

Known oxidation states of xenon are 0, +1, +2, +4, +6 and +8. However, the most stable form is pure xenon, or the xenon's oxidation state of 0. Xenon has 8 stable isotopes and more than 30 unstable isotopes.

Uses

Xenon gas is used in electron tubes, bactericidal lamps, trobe lamps, and lamps used to excite ruby lasers. It has the atomic mass of 131.294 and is the 5th inert gas in the inner gas group.

Xenon is also a trace gas in the atmosphere, occurring at 87 ±1 nL/L (parts per billion) or approximately 1 in 11.5 million. It is also emitted from some mineral springs.

Xenon in shaped Geissler tubes.

Related pages

• Periodic table
• List of common elements