54 iodine ← xenon → caesium Kr ↑ Xe ↓ Rn Periodic table - Extended periodic table
General
Name, symbol, number	xenon, Xe, 54
Chemical series	noble gases
Group, period, block	18, 5, p
Appearance	colorless gas
Standard atomic weight	131.293(6) g·mol−1
Electron configuration	[Kr] 4d10 5s2 5p6
Electrons per shell	2, 8, 18, 18, 8
Physical properties
Phase	gas
Density	(0 °C, 101. Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 Radon (ˈreɪdɒn is the Chemical element that has the symbol Rn and Atomic number 86 This is a typical display of the periodic table of the elements and contains the symbol and Atomic number of each element Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of Chemical elements, sorted by name Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of chemical elements by symbol, including the A table of Chemical elements ordered by Atomic number and color coded according to type of element In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in History Noble gas is translated from the German noun de ''Edelgas'' first used in 1898 by Hugo Erdmann to indicate their extremely low level of reactivity In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in In the Periodic table of the elements, a period is a horizontal row of the table A block of the Periodic table of elements is a set of adjacent groups The respective highest-energy electrons in each element in a block belong to the same Atomic History Noble gas is translated from the German noun de ''Edelgas'' first used in 1898 by Hugo Erdmann to indicate their extremely low level of reactivity A period 5 element is one of the Chemical elements in the fifth row (or period) of the periodic table of the elements. See also Electron configuration The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass To help compare different orders of magnitude, the following list describes various Mass levels between 10&minus36&thinsp kg and 1053&thinspkg Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties This page is about the physical properties of gas as a state of matter The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 325 kPa) 5. 894 g/L
Melting point	(101. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 325 kPa) 161. 4 K (−111. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 7 °C, −169. The Celsius Temperature scale was previously known as the centigrade scale. 1 °F)
Boiling point	(101. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid 325 kPa) 165. 03 K (−108. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 12 °C, −162. The Celsius Temperature scale was previously known as the centigrade scale. 62 °F)
Triple point	161. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 In Thermodynamics, the triple point of a substance is the Temperature and Pressure at which three phases (for example Gas, Liquid 405 K (-112°C), 81. The Celsius Temperature scale was previously known as the centigrade scale. 6[1] kPa
Critical point	289. In Physical chemistry, Thermodynamics, Chemistry and Condensed matter physics, a critical point, also called a critical state 77 K, 5. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 841 MPa
Heat of fusion	(101. The standard Enthalpy of fusion (symbol \Delta{}H_{fus} also known as the heat of fusion or specific melting heat, is the amount of 325 kPa) 2. 27 kJ·mol−1
Heat of vaporization	(101. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material The enthalpy of vaporization, (symbol \Delta{}_{v}H also known as the heat of vaporization or heat of evaporation, is the Energy required 325 kPa) 12. 64 kJ·mol−1
Specific heat capacity	(100 kPa, 25 °C) 20. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the Temperature of a unit quantity 786 J·mol−1·K−1
Vapor pressure P/Pa 1 10 100 1 k 10 k 100 k at T/K 83 92 103 117 137 165
Atomic properties
Crystal structure	cubic face centered
Oxidation states	0, +1, +2, +4, +6, +8 (rarely more than 0) (weakly acidic oxide)
Electronegativity	2. Vapor pressure (also known as equilibrium vapor pressure or saturation vapor pressure) is the Pressure of a Vapor in equilibrium In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. The oxidation number of a central atom in a coordination compound is the charge that it would have if all the Ligands were removed along with the Electron pairs In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons 6 (Pauling scale)
Ionization energies	1st: 1170. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron 4 kJ·mol−1
	2nd: 2046. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material 4 kJ·mol−1
	3rd: 3099. 4 kJ·mol−1
Atomic radius (calc. )	108 pm
Covalent radius	130 pm
Van der Waals radius	216 pm
Miscellaneous
Magnetic ordering	nonmagnetic
Thermal conductivity	(300 K) 5. The covalent radius, r cov is a measure of the size of Atom which forms part of a Covalent bond. Van der Waals Volume The van der Waals volume, V, also called the atomic volume or molecular volume, is the atomic property most directly In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. 65x10-3  W·m−1·K−1
Speed of sound	(liquid) 1090 m/s
CAS registry number	7440-63-3
Selected isotopes
Main article: Isotopes of xenon iso NA half-life DM DE (MeV) DP 124Xe 0. Sound is a vibration that travels through an elastic medium as a Wave. CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to Naturally occurring Xenon ( Xe) is made of nine stable Isotopes (124Xe 134Xe and 136Xe are predicted to undergo Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides In Chemistry, natural abundance (NA refers to the abundance Isotopes of a Chemical element as naturally found on a planet Half-Life (computer-game page here It's already listed in the disambiguation page Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The decay energy is the Energy released by a Nuclear decay. The energy difference of the Reactants is often written as Q: where Q In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a Nuclide 095% 124Xe is stable with 70 neutrons 125Xe syn 16. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 9 h ε 1. The hour (symbol h) is a unit of Time. It is not an SI unit but is accepted for use with the SI Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the 652 125I 126Xe 0. Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic 089% 126Xe is stable with 72 neutrons 127Xe syn 36. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 345 d ε 0. A day (symbol d is a unit of Time equivalent to 24 Hours and the duration of a single Rotation of planet Earth with respect to the Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the 662 127I 128Xe 1. Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic 91% 128Xe is stable with 74 neutrons 129Xe 26. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 4% 129Xe is stable with 75 neutrons 130Xe 4. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 07% 130Xe is stable with 76 neutrons 131Xe 21. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 2% 131Xe is stable with 77 neutrons 132Xe 26. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 9% 132Xe is stable with 78 neutrons 133Xe syn 5. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 247 d β− 0. A day (symbol d is a unit of Time equivalent to 24 Hours and the duration of a single Rotation of planet Earth with respect to the In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 427 133Cs 134Xe 10. Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 4% 134Xe is stable with 80 neutrons 135Xe syn 9. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. A synthetic radioisotope is a Radionuclide that is not found in nature no natural process or mechanism exists which produces it or it is so unstable that it decays away in 14 h β− 1. The hour (symbol h) is a unit of Time. It is not an SI unit but is accepted for use with the SI In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted 16 135Cs 136Xe 8. Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 86% 136Xe is stable with 82 neutrons
References
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Xenon (pronounced /ˈzɛnɒn/^[2] or /'ziːnɒn/^[3]) is the chemical element that has the symbol Xe and atomic number 54. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. Recommended values for many properties of the elements together with various references are collected on these data pages A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. See also Chemical formula. A chemical symbol is an Abbreviation or shortened version of the name of a Chemical element See also List of elements by atomic number In Chemistry and Physics, the atomic number (also known as the proton A colorless, heavy, odorless noble gas, xenon occurs in the earth's atmosphere in trace amounts. History Noble gas is translated from the German noun de ''Edelgas'' first used in 1898 by Hugo Erdmann to indicate their extremely low level of reactivity Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five ^[4] Although generally unreactive, xenon can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called Xenon hexafluoroplatinate is the description of the product obtained from the combination of Platinum hexafluoride and Xenon in an experiment that proved the chemical Noble gas compounds are Chemical compounds that include an element from Group 18 Noble gas ^[5][6][7]

Naturally occurring xenon consists of nine stable isotopes. Naturally occurring Xenon ( Xe) is made of nine stable Isotopes (124Xe 134Xe and 136Xe are predicted to undergo There are also over 40 unstable isotopes that undergo radioactive decay. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. The isotope ratios of xenon are an important tool for studying the early history of the Solar System. The Solar System consists of the Sun and those celestial objects bound to it by Gravity. ^[8] Xenon-135 is produced as a result of nuclear fission and acts as a neutron absorber in nuclear reactors. Nuclear fission is the splitting of the nucleus of an atom into parts (lighter nuclei) often producing Free neutrons and other smaller nuclei which may Neutron absorbers are Isotopes of certain elements that absorb Free neutrons creating heavier isotopes of the same element This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled ^[9]

Xenon is used in flash lamps^[10] and arc lamps,^[11] and as a general anesthetic. A xenon flash lamp is an Electric glow discharge lamp designed to produce extremely intense incoherent, full-spectrum white light for very short durations A xenon arc lamp is an artificial light source Powered by Electricity, it uses Ionized Xenon gas to produce a bright white light that closely In modern medical practice general anaesthesia ( AmE: anesthesia) is a state of total unconsciousness resulting from General anaesthetic drugs ^[12] The first excimer laser design used a xenon dimer molecule (Xe₂) as its lasing medium,^[13] and the earliest laser designs used xenon flash lamps as pumps. An excimer laser (sometimes and more correctly called an exciplex laser) is a form of ultraviolet laser which is commonly used in Eye surgery and Semiconductor A dimer is a Chemical or Biological entity consisting of two subunits called Monomers which are held together by either Intramolecular forces The active laser medium or gain medium is the source of optical Gain within a Laser. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. Laser pumping is the act of energy transfer from an external source into the Gain medium of a Laser. ^[14] Xenon is also being used to search for hypothetical weakly interacting massive particles^[15] and as the propellant for ion thrusters in spacecraft. In Astrophysics, weakly interacting massive particles or WIMPs are hypothetical particles serving as one possible solution to the Dark matter problem A propellant is a material that is used to move ("propel" an object An ion thruster is a form of Electric propulsion used for Spacecraft propulsion that creates thrust by accelerating Ions Ion thrusters are characterized A spacecraft is a Vehicle or machine designed for Spaceflight. ^[16]

Contents 1 History 2 Occurrence 3 Characteristics 4 Isotopes 5 Compounds 6 Applications 6.1 Illumination and optics 6.1.1 Gas-discharge lamps 6.1.2 Lasers 6.2 Anesthesia 6.3 Medical imaging 6.4 Other 7 Precautions 8 See also 9 References 10 External links

History

Xenon was discovered in England by William Ramsay and Morris Travers on July 12, 1898, shortly after their discovery of the elements krypton and neon. Sir William Ramsay (2 October 1852 &ndash 23 July 1916 was a Scottish chemist who discovered the Noble gases and received the Nobel Prize in Morris William Travers (January 24 1872 Kensington London–August 25 1961 Stroud Gloucestershire the founding director of the Indian Institute of Science, was an Events 1191 - Saladin 's garrison surrenders ending the two-year Siege of Acre. Year 1898 ( MDCCCXCVIII) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Common Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 Neon (ˈniːɒn is the Chemical element that has the symbol Ne and Atomic number 10 They found it in the residue left over from evaporating components of liquid air. Liquid Air was the brand name of an unusual Automobile produced by a joint American / English concern between 1899 and 1902 ^[17][18] Ramsay suggested the name xenon for this gas from the Greek word ξένον [xenon], neuter singular form of ξένος [xenos], meaning foreign, strange, or host. Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly ^[19][20] In 1902, Ramsay estimated the proportion of xenon in the Earth's atmosphere as one part in 20 million. ^[21]

During the 1930s, engineer Harold Edgerton began exploring strobe light technology for high speed photography. For the police officer see Harry Edgerton Harold Eugene "Doc" Edgerton ( April 6, 1903 &ndash January High Speed Photography is the science of taking pictures of very fast phenomena This led him to the invention of the xenon flash lamp, in which light is generated by sending a brief electrical current through a tube filled with xenon gas. A xenon flash lamp is an Electric glow discharge lamp designed to produce extremely intense incoherent, full-spectrum white light for very short durations In 1934, Edgerton was able to generate flashes as brief as one microsecond with this method. To help compare Orders of magnitude of different Times this page lists times between 10&minus6 seconds and 10&minus5 seconds (1 micro ^[10][22][23]

In 1939 Albert R. Behnke Jr. began exploring the causes of "drunkenness" in deep-sea divers. He tested the effects of varying the breathing mixtures on his subjects, and discovered that this caused the divers to perceive a change in depth. From his results, he deduced that xenon gas could serve as an anesthetic. Anesthesia, or anaesthesia (see spelling differences; from Greek grc αν- an-, "without" and grc αἲσθησις Although Lazharev, in Russia, apparently studied xenon anesthesia in 1941, the first published report confirming xenon anesthesia was in 1946 by J. Anesthesia, or anaesthesia (see spelling differences; from Greek grc αν- an-, "without" and grc αἲσθησις H. Lawrence, who experimented on mice. Xenon was first used as a surgical anesthetic in 1951 by Stuart C. Cullen, who successfully operated on two patients. ^[24]

In 1960 physicist John H. Reynolds discovered that certain meteorites contained an isotopic anomaly in the form of an overabundance of xenon-129. John Hamilton Reynolds ( April 3, 1923 &ndash November 4, 2000) was an American Physicist and a specialist in Mass A meteorite is a natural object originating in Outer space that survives an impact with the Earth 's surface He inferred that this was a decay product of radioactive iodine-129. In Nuclear physics, a decay product, also known as a daughter product, daughter isotope or daughter nuclide, is a Nuclide Iodine-129 (129I is a Radioisotope of Iodine. Formation and decay 129I is primarily formed from the Fission This isotope is produced slowly by cosmic ray spallation and nuclear fission, but is produced in quantity only in supernova explosions. Cosmic ray spallation is a form of naturally occurring Nuclear fission and Nucleosynthesis. Nuclear fission is the splitting of the nucleus of an atom into parts (lighter nuclei) often producing Free neutrons and other smaller nuclei which may As the half-life of ¹²⁹I is comparatively short on a cosmological time scale, only 16 million years, this demonstrated that only a short time had passed between the supernova and the time the meteorites had solidified and trapped the ¹²⁹I. These two events (supernova and solidification of gas cloud) were inferred to have happened during the early history of the Solar System, as the ¹²⁹I isotope was likely generated before the Solar System was formed, but not long before, and seeded the solar gas cloud isotopes with isotopes from a second source. The Solar System consists of the Sun and those celestial objects bound to it by Gravity. This supernova source may also have caused collapse of the solar gas cloud. ^[25][26]

Xenon and the other noble gases were for a long time considered to be completely chemically inert and not able to form compounds. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. However, while teaching at the University of British Columbia, Neil Bartlett discovered that the gas platinum hexafluoride (PtF₆) was a powerful oxidizing agent that could oxidize oxygen gas (O₂) to form dioxygenyl hexafluoroplatinate (O₂⁺[PtF₆]⁻). The University of British Columbia ( UBC) is a Canadian public research University with campuses near Vancouver and in Kelowna For the playwright see Neil Bartlett. Neil Bartlett was a chemist best known for his discovery of Noble gas compounds He taught Platinum hexafluoride is the Chemical compound with the formula Pt[[Fluorine F6]] Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state The dioxygenyl Ion, O2+ is a rarely-encountered Oxycation in which both Oxygen Atoms have an Oxidation state ^[27] Since O₂ and xenon have almost the same first ionization potential, Bartlett realized that platinum hexafluoride might also be able to oxidize xenon. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron On March 23, 1962, he mixed the two gases and produced the first known compound of a noble gas, xenon hexafluoroplatinate. Events 1174 - Jocelin, Abbot of Melrose, is elected Bishop of Glasgow. Year 1962 ( MCMLXII) was a Common year starting on Monday (the link is to a full 1962 calendar of the Gregorian calendar. Xenon hexafluoroplatinate is the description of the product obtained from the combination of Platinum hexafluoride and Xenon in an experiment that proved the chemical ^[28][7] Bartlett thought its composition to be Xe⁺[PtF₆]⁻, although later work has revealed that it was probably a mixture of various xenon-containing salts. ^[29][30][31] Since then, many other xenon compounds have been discovered,^[32] and some compounds of the noble gases argon, krypton, and radon have been identified, including argon fluorohydride (HArF),^[33] krypton difluoride (KrF₂),^[34][35] and radon fluoride. This article pertains to the chemical element For other uses see Argon (disambiguation. Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 Radon (ˈreɪdɒn is the Chemical element that has the symbol Rn and Atomic number 86 Argon fluorohydride (HArF is the first known compound of the Chemical element Argon. See also Krypton fluoride laser Krypton difluoride, KrF2 was the first compound of Krypton discovered Radon difluoride ( is a compound of Radon, a Noble gas. Radon reacts readily with Fluorine to form a solid compound but this decomposes on attempted vaporization ^[36]

Occurrence

Xenon is a trace gas in Earth's atmosphere, occurring at 0. The term Trace gas refers to a gas or gases which make up less than 1% by volume of the Earth's atmosphere, and therefore includes all gases except Nitrogen (78 Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five 087±0. 001 parts per million (μL/L),^[37] and is also found in gases emitted from some mineral springs. "Parts-per" notation is used especially in Science and Engineering, to denote Ratios (relative proportions in measured quantities particularly A spring is a point where Groundwater flows out of the ground and is thus where the Aquifer surface meets the ground surface Some radioactive species of xenon, for example, ¹³³Xe and ¹³⁵Xe, are produced by neutron irradiation of fissionable material within nuclear reactors. This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled ^[5]

Xenon is obtained commercially as a byproduct of the separation of air into oxygen and nitrogen. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 After this separation, generally performed by fractional distillation in a double-column plant, the liquid oxygen produced will contain small quantities of krypton and xenon. Fractional distillation is the separation of a mixture into its component parts or fractions such as in separating Chemical compounds by their Boiling point by heating By additional fractional distillation steps, the liquid oxygen may be enriched to contain 0. 1–0. 2% of a krypton/xenon mixture, which is extracted either via adsorption onto silica gel or by distillation. Silica gel is a granular porous form of Silica made synthetically from Sodium silicate. Finally, the krypton/xenon mixture may be separated into krypton and xenon via distillation. Krypton (ˈkrɪptən or /ˈkrɪptɒn/ from kryptos "hidden" is a Chemical element with the symbol Kr and Atomic number 36 ^[38][39] Extraction of a liter of xenon from the atmosphere requires 220 watt-hours of energy. ^[40] Worldwide production of xenon in 1998 was estimated at 5,000–7,000 m³. ^[41] Due to its low abundance, xenon is much more expensive than the lighter noble gases—approximate prices for the purchase of small quantities in Europe in 1999 were 10 €/L for xenon, 1 €/L for krypton, and 0. Please update other articles as well to avoid contradiction within Wikipedia e 20 €/L for neon. ^[41]

Xenon is relatively rare in the Sun's atmosphere, on Earth, and in asteroids and comets. The Sun (Sol is the Star at the center of the Solar System. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 Asteroids, sometimes called Minor planets or planetoids', are bodies—primarily of the inner Solar System —that are smaller than planets but A comet is a small Solar System body that orbits the Sun and when close enough to the Sun exhibits a visible coma (atmosphere or a tail — The atmosphere of Mars shows a xenon abundance similar to that of Earth: 0. Structure Mars' atmosphere is composed of the following major divisions Lower Atmosphere This is a warm region affected by heat from airborne Dust and 08 parts per million,^[42] however Mars shows a higher proportion of ¹²⁹Xe than the Earth or the Sun. As this isotope is generated by radioactive decay, the result may indicate that Mars lost most of its primordial atmosphere, possibly within the first 100 million years after the planet was formed. ^[43][44] By contrast, the planet Jupiter has an unusually high abundance of xenon in its atmosphere; about 2. 6 times as much as the Sun. ^[45] This high abundance remains unexplained and may have been caused by an early and rapid buildup of planetesimals—small, subplanetary bodies—before the presolar disk began to heat up. Planetesimals are solid objects thought to exist in Protoplanetary disks and in Debris disks A widely accepted theory of planet formation the so-called planetesimal The formation and evolution of the Solar System is estimated to have begun ^[46] (Otherwise, xenon would not have been trapped in the planetesimal ices. ) Within the Solar System, the nucleon fraction for all isotopes of xenon is 1. The Solar System consists of the Sun and those celestial objects bound to it by Gravity. In Physics a nucleon is a collective name for two Baryons the Neutron and the Proton. 56 × 10^-8, or one part in 64 million of the total mass. ^[47] The problem of the low terrestrial xenon may potentially be explained by covalent bonding of xenon to oxygen within quartz, hence reducing the outgassing of xenon into the atmosphere. Quartz (from German) is the most abundant Mineral in the Earth 's Continental crust (although Feldspar is more common in ^[48]

Unlike the lower mass noble gases, the normal stellar nucleosynthesis process inside a star does not form xenon. Stellar nucleosynthesis is the collective term for the nuclear reactions taking place in Stars to build the nuclei of the heavier elements. Elements more massive than iron-56 have a net energy cost to produce through fusion, so there is no energy gain for a star to create xenon. Iron-56 is the most common Isotope of Iron. About 91754% of all iron is iron-56 ^[49] Instead, many isotopes of xenon are formed during supernova explosions. A supernova (plural supernovae or supernovas) is a stellar Explosion. ^[50]

Characteristics

An atom of xenon is defined as having a nucleus with 54 protons. The proton ( Greek πρῶτον / proton "first" is a Subatomic particle with an Electric charge of one positive At standard temperature and pressure, pure xenon gas has a density of 5. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made 761 kg/m³, about 4. 5 times the surface density of the Earth's atmosphere, 1. 217 kg/m³. ^[51] As a liquid, xenon has a density of up to 3. 100 g/mL, with the density maximum occurring at the triple point. ^[52] Under the same conditions, the density of solid xenon, 3. 640 g/cm³, is larger than the average density of granite, 2. Granite (ˈɡrænɪt is a common and widely occurring type of intrusive, Felsic, igneous rock. 75 g/cm³. ^[52] Using gigapascals of pressure, xenon has been forced into a metallic phase. Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface ^[53]

Xenon is a member of the zero-valence elements that are called noble or inert gases. In Chemistry, valence, also known as valency or valency number, is a measure of the number of Chemical bonds formed by the Atoms History Noble gas is translated from the German noun de ''Edelgas'' first used in 1898 by Hugo Erdmann to indicate their extremely low level of reactivity In English to be inert is to be in a state of doing little or nothing This page is about the physical properties of gas as a state of matter It is inert to most common chemical reactions (such as combustion, for example) because the outer valence shell contains eight electrons. An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. This produces a stable, minimum energy configuration in which the outer electrons are tightly bound. ^[54] However, xenon can be oxidized by powerful oxidizing agents, and many xenon compounds have been synthesized. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state

In a gas-filled tube, xenon emits a blue or lavenderish glow when the gas is excited by electrical discharge. A gas-filled tube, also known as a discharge tube, is an arrangement of Electrodes in a Gas within an insulating, temperature-resistant Envelope Blue is a Colour, the Perception of which is evoked by Lavender is a pale Tint of violet. It applies particularly to the Color of the flower of the same name. An electric arc is an Electrical breakdown of a gas which produces an ongoing plasma discharge, resulting from a current flowing through normally nonconductive Xenon emits a band of emission lines that span the visual spectrum,^[55] but the most intense lines occur in the region of blue light, which produces the coloration. A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range compared ^[56]

Isotopes

Main article: Isotopes of xenon

Naturally occurring xenon is made of nine stable isotopes. Naturally occurring Xenon ( Xe) is made of nine stable Isotopes (124Xe 134Xe and 136Xe are predicted to undergo Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides The isotopes ¹²⁴Xe, ¹³⁴Xe and ¹³⁶Xe are predicted to undergo double beta decay, but this has never been observed so they are considered to be stable. In the process of Beta decay, unstable nuclei decay by converting a Neutron in the nucleus to a Proton and emitting an Electron and an electron ^[57][58] Besides these stable forms, there are over 40 unstable isotopes that have been studied. ¹²⁹Xe is produced by beta decay of ¹²⁹I, which has a half-life of 16 million years, while ^131mXe, ¹³³Xe, ^133mXe, and ¹³⁵Xe are some of the fission products of both ²³⁵U and ²³⁹Pu,^[59] and therefore used as indicators of nuclear explosions. In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic Half-Life (computer-game page here It's already listed in the disambiguation page Nuclear fission is the splitting of the nucleus of an atom into parts (lighter nuclei) often producing Free neutrons and other smaller nuclei which may Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the The various isotopes of xenon are produced from supernova explosions,^[50] red giant stars that have exhausted the hydrogen at their cores and entered the asymptotic giant branch, classical novae explosions^[60] and the radioactive decay of elements such as iodine, uranium and plutonium. A supernova (plural supernovae or supernovas) is a stellar Explosion. A red giant is a luminous Giant star of low or intermediate mass (roughly 0 The asymptotic giant branch is the region of the Hertzsprung-Russell diagram populated by evolving low to medium-mass Stars This is a period of Stellar evolution A nova (pl novae or novas) is a Cataclysmic nuclear explosion caused by the accretion of hydrogen onto the surface of a White Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic Uranium (jʊˈreɪniəm is a silvery-gray Metallic Chemical element in the ^[59]

The artificial isotope ¹³⁵Xe is of considerable significance in the operation of nuclear fission reactors. 135Xe is an isotope of Xenon, and a Fission product (yield 63333% which is the most powerful known Neutron -absorbing Nuclear poison and has This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled ¹³⁵Xe has a huge cross section for thermal neutrons, 2. The total neutron cross section of an isotope of a Chemical element is the effective cross sectional area that an atom of that isotope presents to Neutron scattering The neutron temperature, also called the neutron energy, indicates a free neutron's Kinetic energy, usually given in Electron volts The term 6×10⁶ barns,^[9] so it acts as a neutron absorber or "poison" that can slow or stop the chain reaction after a period of operation. A barn (symbol b) is a unit of Area. While the barn is not an SI unit it is accepted (although discouraged for use with the SI Neutron absorbers are Isotopes of certain elements that absorb Free neutrons creating heavier isotopes of the same element A nuclear poison, also called a neutron poison is a substance with a large neutron absorption cross-section in applications such as Nuclear reactors This was discovered in the earliest nuclear reactors built by the American Manhattan Project for plutonium production. The World War II Manhattan Project developed the first Nuclear weapon (atomic bomb Fortunately the designers had made provisions in the design to increase the reactor's reactivity (the number of neutrons per fission that go on to fission other atoms of nuclear fuel). Nuclear fuel is any material that can be consumed to derive Nuclear energy, by analogy to chemical Fuel that is burned to derive energy ^{[61] 135}Xe reactor poisoning played a major role in the Chernobyl disaster. The Chernobyl disaster was a nuclear reactor accident in the Chernobyl Nuclear Power Plant in the Soviet Union. ^[62]

Under adverse conditions, relatively high concentrations of radioactive xenon isotopes may be found emanating from nuclear reactors due to the release of fission products from cracked fuel rods,^[63] or fissioning of uranium in cooling water. Water cooling is a method of Heat removal from components As opposed to Air cooling, Water is used as the heat transmitter ^[64]

Because xenon is a tracer for two parent isotopes, xenon isotope ratios in meteorites are a powerful tool for studying the formation of the solar system. A meteorite is a natural object originating in Outer space that survives an impact with the Earth 's surface The formation and evolution of the Solar System is estimated to have begun The iodine-xenon method of dating gives the time elapsed between nucleosynthesis and the condensation of a solid object from the solar nebula. Radiometric dating (often called radioactive dating) is a technique used to date materials usually based on a comparison between the observed abundance of a naturally occurring Nucleosynthesis is the process of creating new atomic nuclei from preexisting Nucleons (protons and neutrons The formation and evolution of the Solar System is estimated to have begun Xenon isotopic ratios such as ¹²⁹Xe/¹³⁰Xe and ¹³⁶Xe/¹³⁰Xe are also a powerful tool for understanding terrestrial differentiation and early outgassing. ^[8] Excess ¹²⁹Xe 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. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single New Mexico ( is a state located in the southwestern region of the United States of America. The mantle is a part of an Astronomical object. The interior of the Earth, similar to the other Terrestrial planets, is Chemically divided ^[65][59]

Compounds

See also: Category:Xenon compounds

Xenon hexafluoroplatinate was the first chemical compound of xenon, synthesized in 1962. Xenon tetrafluoride, Xe[[Fluorine F4]] is one of the chemical compounds derived from the Noble gas xenon Xenon hexafluoroplatinate is the description of the product obtained from the combination of Platinum hexafluoride and Xenon in an experiment that proved the chemical A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. ^[28] Following this, many additional compounds of xenon have been discovered. These include xenon difluoride (XeF₂), xenon tetrafluoride (XeF₄), xenon hexafluoride (XeF₆), xenon tetroxide (XeO₄), and sodium perxenate (Na₄XeO₆). Xenon difluoride is a powerful Fluorinating agent, with the chemical formula, is one of the most stable Xenon compounds. Xenon tetrafluoride, Xe[[Fluorine F4]] is one of the chemical compounds derived from the Noble gas xenon Xenon hexafluoride is the Chemical compound with the formula XeF6 Xenon tetroxide (molecular formula XeO4) is a yellow Crystalline Solid that is stable below −35 Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 The perxenates are salts of Perxenic acid, H 4 Xe[[oxygen O]]6 A highly explosive compound, xenon trioxide (XeO₃), has also been made. An explosive material is a material that either is chemically or otherwise Energetically unstable or produces a sudden expansion of the material usually accompanied Xenon trioxide is an unstable compound of Xenon in its +6 Oxidation state. Most of the more than 80^[66][67] xenon compounds found to date contain electronegative fluorine or oxygen. When other atoms are bound (such as hydrogen or carbon), they are often part of a molecule containing fluorine or oxygen. Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 ^[68] Some compounds of xenon are colored but most are colorless. ^[66]

In 1995, a group of scientists at the University of Helsinki in Finland (M. The University of Helsinki (Helsingin yliopisto Helsingfors universitet is a University located in Helsinki, Finland since 1829 but founded Finland, officially the Republic of Finland ( is a Nordic country situated in the Fennoscandian region of northern Europe. Räsänen and co-workers) announced the preparation of xenon dihydride (HXeH), and later xenon hydride-hydroxide (HXeOH), hydroxenoacetylene (HXeCCH), and other Xe-containing molecules. ^[69][70] Deuterated molecules, HXeOD and DXeOH, have also been produced. Deuterium, also called heavy hydrogen, is a Stable isotope of Hydrogen with a Natural abundance in the Oceans of Earth ^[71]

As well as compounds where xenon forms a chemical bond, xenon can form clathrates—substances where xenon atoms are trapped by the crystalline lattice of another compound. A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic A clathrate or clathrate compound or cage compound is a Chemical substance consisting of a lattice of one type of molecule trapping In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. An example is xenon hydrate (Xe·5. Clathrate hydrates (or gas clathrates gas hydrates clathrates hydrates etc were first documented in 1810 by Sir Humphrey Davy; they are crystalline 75 H₂O), where xenon atoms occupy vacancies in a lattice of water molecules. ^[72] The deuterated version of this hydrate has also been produced. Hydrate is a term used in Inorganic chemistry and Organic chemistry to indicate that a substance contains Water. ^[73] Such clathrate hydrates can occur naturally under conditions of high pressure, such as in Lake Vostok underneath the Antarctic ice sheet. Clathrate hydrates (or gas clathrates gas hydrates clathrates hydrates etc were first documented in 1810 by Sir Humphrey Davy; they are crystalline Lake Vostok (восток "east" is the largest of more than 140 subglacial Lakes found under the surface of Earth's southern-most ^[74] Clathrate formation can be used to fractionally distill xenon, argon and krypton. ^[75] Xenon can also form endohedral fullerene compounds, where a xenon atom is trapped inside a fullerene molecule. "C60" and "C-60" redirect here For other uses see C60 (disambiguation. The xenon atom trapped in the fullerene can be monitored via ¹²⁹Xe nuclear magnetic resonance spectroscopy. Using this technique, chemical reactions on the fullerene molecule can be analyzed, due to the sensitivity of the chemical shift of the xenon atom to its environment. In Nuclear magnetic resonance (NMR the chemical shift describes the dependence of nuclear magnetic energy levels on the electronic environment in a Molecule. However, the xenon atom also has an electronic influence on the reactivity of the fullerene. ^[76]

Applications

Although xenon is rare and relatively expensive to extract from the Earth's atmosphere, it still has a number of applications. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five

Illumination and optics

Gas-discharge lamps

Xenon is used in light-emitting devices called xenon flash lamps, which are used in photographic flashes and stroboscopic lamps;^[10] to excite the active medium in lasers which then generate coherent light;^[77] and, occasionally, in bactericidal lamps. A xenon flash lamp is an Electric glow discharge lamp designed to produce extremely intense incoherent, full-spectrum white light for very short durations A flash is a device used in Photography that produces an instantaneous flash of artificial Light The active laser medium or gain medium is the source of optical Gain within a Laser. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. In Physics, coherence is a property of waves that enables stationary (i A bactericide or bacteriocide is a substance that kills bacteria and preferably nothing else ^[78] The first solid-state laser, invented in 1960, was pumped by a xenon flash lamp,^[14] and lasers used to power inertial confinement fusion are also pumped by xenon flash lamps. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. Inertial confinement fusion ( ICF) is a process where Nuclear fusion reactions are initiated by heating and compressing a fuel target typically in the form of ^[79]

Continuous, short-arc, high pressure xenon arc lamps have a color temperature closely approximating noon sunlight and are used in solar simulators. A xenon arc lamp is an artificial light source Powered by Electricity, it uses Ionized Xenon gas to produce a bright white light that closely Color temperature is a characteristic of Visible light that has important applications in lighting photography videography publishing and other fields That is, the chromaticity of these lamps closely approximates a heated black body radiator that has a temperature close to that observed from the Sun. Chromaticity is an objective specification of the Quality of a Color regardless of its luminance that is as determined by its Colorfulness (or saturation In Physics, a black body is an object that absorbs all light that falls on it After they were first introduced during the 1940s, these lamps began replacing the shorter-lived carbon arc lamps in movie projectors. ^[11] They are employed in typical 35mm and IMAX film projection systems, automotive HID headlights and other specialized uses. 35 mm film is the basic Film gauge most commonly used for both still Photography and Motion pictures, and remains relatively unchanged since its IMAX (short for Image MAXimum is a Film format created by Canada 's IMAX Corporation that has the capacity to display images of far greater size and This article is concerned with technical aspects of moving film projection A High-intensity discharge (HID lamp is a type of electrical lamp which produces light by means of an electric arc between Tungsten Electrodes These arc lamps are an excellent source of short wavelength ultraviolet radiation and they have intense emissions in the near infrared, which is used in some night vision systems. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of Night vision is the ability to see in a dark environment Whether by biological or technological means night vision is made possible by a combination of two approaches sufficient

The individual cells in a plasma display use a mixture of xenon and neon that is converted into a plasma using electrodes. A plasma display panel (PDP is a type of Flat panel display now commonly used for large TV displays (typically above 37-inch or 940 mm In Physics and Chemistry, plasma is an Ionized Gas, in which a certain proportion of Electrons are free rather than being bound An electrode is an Electrical conductor used to make contact with a nonmetallic part of a circuit (e The interaction of this plasma with the electrodes generates ultraviolet photons, which then excite the phosphor coating on the front of the display. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena A phosphor is a substance that exhibits the phenomenon of Phosphorescence (sustained glowing after exposure to energized particles such as Electrons ^[80][81]

Xenon is used as a "starter gas" in high pressure sodium lamps. A sodium vapor lamp is a Gas discharge lamp which uses Sodium in an excited state to produce Light It has the lowest thermal conductivity and lowest ionization potential of all the non-radioactive noble gases. In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron As a noble gas, it does not interfere with the chemical reactions occurring in the operating lamp. The low thermal conductivity minimizes thermal losses in the lamp while in the operating state, and the low ionization potential causes the breakdown voltage of the gas to be relatively low in the cold state, which allows the lamp to be more easily started. Breakdown Voltage of an Insulator is the minimum voltage that causes a portion of an insulator to become electrically conductive. ^[82]

Lasers

In 1962, a group of researchers at Bell Laboratories discovered laser action in xenon,^[83] and later found that the laser gain was improved by adding helium to the lasing medium. Bell Laboratories (also known as Bell Labs and formerly known as AT&T Bell Laboratories and Bell Telephone Laboratories) is the Research organization Helium ( He) is a colorless odorless tasteless non-toxic Inert Monatomic Chemical ^[84][85] The first excimer laser used a xenon dimer (Xe₂) energized by a beam of electrons to produce stimulated emission at an ultraviolet wavelength of 176 nm. An excimer laser (sometimes and more correctly called an exciplex laser) is a form of ultraviolet laser which is commonly used in Eye surgery and Semiconductor A dimer is a Chemical or Biological entity consisting of two subunits called Monomers which are held together by either Intramolecular forces In Optics, stimulated emission is the process by which an electron perturbed by a Photon having the correct energy may drop to a lower Energy level resulting Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays A nanometre ( American spelling: nanometer, symbol nm) ( Greek: νάνος nanos dwarf; μετρώ metrό count) is a ^[13] Xenon chloride and xenon fluoride have also been used in excimer (or, more accurately, exciplex) lasers. ^[86] The xenon chloride excimer laser has been employed, for example, in certain dermatological uses. ^[87]

Anesthesia

Xenon has been used as a general anaesthetic, although it is expensive. A general anaesthetic (or anesthetic, see Spelling differences) drug is an anaesthetic drug that brings about a reversible loss of Consciousness. Even so, anesthesia machines that can deliver xenon are about to appear on the European market. ^[88] Two mechanisms for xenon anesthesia have been proposed. The first one involves the inhibition of the calcium ATPase pump—the mechanism cells use to remove calcium (Ca²⁺)—in the cell membrane of synapses. The cell membrane (also called the plasma membrane, plasmalemma, or "phospholipid bilayer" is a Selectively permeable Lipid bilayer Chemical synapses are specialized junctions through which Neurons signal to each other and to non-neuronal cells such as those in Muscles or Glands ^[89] This results from a conformational change when xenon binds to nonpolar sites inside the protein. In Chemistry, conformational isomerism is a form of Stereoisomerism in which Molecules with the same Structural formula (same connectivity ^[90] The second mechanism focuses on the non-specific interactions between the anesthetic and the lipid membrane. A lipid bilayer or bilayer lipid membrane ( BLM) is a membrane composed of Lipid molecules (usually Phospholipids. ^[91]

Xenon has a minimum alveolar concentration (MAC) of 71%, making it 50% more potent than N₂O as an anesthetic. Minimum alveolar concentration or MAC is a concept used to compare the strengths of anaesthetic vapours; in simple terms it is defined as the concentration of ^[12] Thus it can be used in concentrations with oxygen that have a lower risk of hypoxia. Chronic Hypoxia is a pathological condition in which the body as a whole ( generalized hypoxia) or region of the body ( tissue hypoxia) is deprived of adequate Unlike nitrous oxide (N₂O), xenon is not a greenhouse gas and so it is also viewed as environmentally friendly. Nitrous oxide, commonly known as " laughing gas," is a Chemical compound with the Chemical formula N 2 O. Greenhouse gases are gaseous constituents of the atmosphere bothnatural and anthropogenic that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared Environmental friendly, eco-friendly, and nature friendly are synonyms used to refer to Goods and services considered to inflict minimal harm Because of the high cost of xenon, however, economic application will require a closed system so that the gas can be recycled, with the gas being appropriately filtered for contaminants between uses. ^[40]

Medical imaging

Gamma emission from the radioisotope ¹³³Xe of xenon can be used to image the heart, lungs, and brain, for example, by means of single photon emission computed tomography. Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions A radionuclide is an Atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created Single photon emission computed tomography (SPECT or less commonly SPET is a Nuclear medicine tomographic imaging technique using Gamma rays. ¹³³Xe has also been used to measure blood flow. Blood flow is the flow of Blood in the Cardiovascular system. ^[92][93][94]

Nuclei of two of the stable isotopes of xenon, ¹²⁹Xe and ¹³¹Xe, have non-zero intrinsic angular momenta (nuclear spins). Naturally occurring Xenon ( Xe) is made of nine stable Isotopes (124Xe 134Xe and 136Xe are predicted to undergo In Physics, the angular momentum of a particle about an origin is a vector quantity equal to the mass of the particle multiplied by the Cross product of the position In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin When mixed with alkali vapor and nitrogen and exposed to a laser beam of circularly-polarized light that is tuned to an absorption line of the alkali atoms, their nuclear spins can be aligned by a spin exchange process in which the alkali valence electrons are spin-polarized by the light and then transfer their polarization to the xenon nuclei via magnetic hyperfine coupling. In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. In Electrodynamics, circular polarization (also circular polarisation) of Electromagnetic radiation is a Polarization such that the tip of the A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range compared ^[95] Typically, pure rubidium metal, heated above 100 °C, is used to produce the alkali vapor. Rubidium (ruːˈbɪdiəm /rəˈbɪdiəm/ is a Chemical element with the symbol Rb and Atomic number 37 The Celsius Temperature scale was previously known as the centigrade scale. In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal The resulting spin polarization of xenon nuclei can surpass 50% of its maximum possible value, greatly exceeding the equilibrium value dictated by the Boltzmann distribution (typically 0. Spin polarization is the degree to which the spin, ie the intrinsic Angular momentum of elementary particles is aligned with a given direction The nucleus of an Atom is the very dense region consisting of Nucleons ( Protons and Neutrons, at the center of an atom WikipediaWikiProject Probability#Standards for a discussion of standards used for probability distribution articles such as this one 001% of the maximum value at room temperature, even in the strongest magnets). Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed A magnet (from Greek grc μαγνήτης λίθος " Magnesian stone" is a material or object that produces a Magnetic field. Such non-equilibrium alignment of spins is a temporary condition, and is called hyperpolarization. Hyperpolarization is the nuclear spin polarization of a material far beyond Thermal equilibrium conditions

Because a ¹²⁹Xe nucleus has a spin of 1/2, and therefore a zero electric quadrupole moment, the ¹²⁹Xe nucleus does not experience any quadrupolar interactions during collisions with other atoms, and thus its hyperpolarization can be maintained for long periods of time even after the laser beam has been turned off and the alkali vapor removed by condensation on a room-temperature surface. In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin In Physics, the space surrounding an Electric charge or in the presence of a time-varying Magnetic field has a property called an electric field (that can A quadrupole or quadrapole is one of a sequence of configurations of — for example — electric charge or current or gravitational mass that can exist in ideal form but it The time it takes for a collection of spins to return to their equilibrium (Boltzmann) polarization is called the T₁ relaxation time. In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin Spin polarization is the degree to which the spin, ie the intrinsic Angular momentum of elementary particles is aligned with a given direction Spin-lattice relaxation time, known as T1, is a time constant in Nuclear Magnetic Resonance and Magnetic Resonance Imaging. For ¹²⁹Xe it can range from several seconds for xenon atoms dissolved in blood^[96] to several hours in the gas phase^[97] and several days in deeply-frozen solid xenon. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties ^[98] In contrast, ¹³¹Xe has a nuclear spin value of 3/2 and a nonzero quadrupole moment, and has T₁ relaxation times in the millisecond and second ranges. Naturally occurring Xenon ( Xe) is made of nine stable Isotopes (124Xe 134Xe and 136Xe are predicted to undergo A quadrupole or quadrapole is one of a sequence of configurations of — for example — electric charge or current or gravitational mass that can exist in ideal form but it A millisecond (from Milli- and Second; abbreviation ms is one thousandth of a Second. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units ^[99] Hyperpolarization renders ¹²⁹Xe much more detectable via magnetic resonance imaging and has been used for studies of the lungs and other tissues. Hyperpolarization is the nuclear spin polarization of a material far beyond Thermal equilibrium conditions It can be used, for example, to trace the flow of gases within the lungs. ^[100][101]

Other

In nuclear energy applications, xenon is used in bubble chambers,^[102] probes, and in other areas where a high molecular weight and inert nature is desirable. Nuclear Energy is released by the splitting (fission or merging together (fusion of the nuclei of Atom (s A bubble chamber is a vessel filled with a superheated transparent Liquid (most often Liquid hydrogen) used to detect electrically charged The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one

Liquid xenon is being used as a medium for detecting hypothetical weakly interacting massive particles, or WIMPs. In Astrophysics, weakly interacting massive particles or WIMPs are hypothetical particles serving as one possible solution to the Dark matter problem When a WIMP collides with a xenon nucleus, it should, theoretically, strip an electron and create a primary scintillation. Scintillation is a flash of Light produced in a transparent material by an Ionization event By using xenon, this burst of energy could then be readily distinguished from similar events caused by particles such as cosmic rays. For the 1962 Bruce Conner film see Cosmic Ray (film Cosmic rays are energetic particles originating from space that impinge on ^[15] However, the XENON experiment at the Gran Sasso National Laboratory in Italy has thus far failed to find any confirmed WIMPs. The Laboratori Nazionali del Gran Sasso is a Particle physics laboratory of the INFN, situated near the Gran Sasso Mountain in Italy Even if no WIMPs are detected, the experiment will serve to constrain the properties of dark matter and some physics models. In Physics and cosmology, dark matter is hypothetical Matter that does not interact with the electromagnetic force but whose presence can be inferred from ^[103] The current detector at this facility is five times as sensitive as other instruments world-wide, and the sensitivity will be increased by an order of magnitude in 2008. An order of magnitude is the class of scale or magnitude of any amount where each class contains values of a fixed ratio to the class preceding it ^[104]

Xenon is the preferred fuel for ion propulsion of spacecraft because of its low ionization potential per atomic weight, and its ability to be stored as a liquid at near room temperature (under high pressure) yet be easily converted back into a gas to fuel the engine. An ion thruster is a form of Electric propulsion used for Spacecraft propulsion that creates thrust by accelerating Ions Ion thrusters are characterized A spacecraft is a Vehicle or machine designed for Spaceflight. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass Room temperature (also referred to as ambient temperature) is a common term to denote a certain Temperature within enclosed space at which humans are accustomed The inert nature of xenon makes it environmentally friendly and less corrosive to an ion engine than other fuels such as mercury or caesium. An ion thruster is a form of Electric propulsion used for Spacecraft propulsion that creates thrust by accelerating Ions Ion thrusters are characterized Mercury (ˈmɜrkjʊri also called quicksilver or hydrargyrum, is a Chemical element with the symbol Hg ( Latinized hydrargyrum Caesium or cesium (ˈsiːziəm is the Chemical element with the symbol Cs and Atomic number 55 Xenon was first used for satellite ion engines during the 1970s. ^[105] It was later employed as a propellant for Europe's SMART-1 spacecraft^[16] and for the three ion propulsion engines on NASA's Dawn Spacecraft. SMART-1 was a Swedish -designed European Space Agency Satellite that Orbited around the Moon. Dawn, launched on September 27 2007 is a Robotic spacecraft being sent by NASA on a Space exploration mission to the two most massive members ^[106]

Chemically, the perxenate compounds are used as oxidizing agents in analytical chemistry. The perxenates are salts of Perxenic acid, H 4 Xe[[oxygen O]]6 An oxidizing agent or oxidising agent (also called an oxidant, oxidizer or oxidiser) can be defined as either a Chemical compound Analytical chemistry is the study of the Chemical composition of natural and artificial Materials. Xenon difluoride is used as an etchant for silicon, particularly in the production of microelectromechanical systems (MEMS). Xenon difluoride is a powerful Fluorinating agent, with the chemical formula, is one of the most stable Xenon compounds. Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14 Microelectromechanical systems ( MEMS) is the technology of the very small and merges at the nano-scale into Nanoelectromechanical systems (NEMS and Nanotechnology ^[107] The anticancer drug 5-fluorouracil can be produced by reacting xenon difluoride with uracil. Fluorouracil (5-FU or f5U is a Pyrimidine analog, which is used as a drug in the treatment of Cancer. Uracil is a common and naturally occurring Pyrimidine derivative ^[108] Xenon is also used in protein crystallography. X-ray crystallography is a method of determining the arrangement of Atoms within a Crystal, in which a beam of X-rays strikes a crystal and scatters Applied at pressures from 0. 5 to 5 MPa (5 to 50 atm) to a protein crystal, xenon atoms bind in predominantly hydrophobic cavities, often creating a high quality, isomorphous, heavy-atom derivative, which can be used for solving the phase problem. The Standard atmosphere is an international reference pressure defined as 101325 Pa and formerly used as unit of Pressure (symbol atm In Chemistry, hydrophobicity (from the combining form of water in Attic Greek hydro- and for fear phobos) refers to the physical property of The phase problem is the name given to the problem of loss of information (the phase from a physical measurement ^[109][110]

Precautions

Xenon gas can be safely kept in normal sealed glass or metal containers at standard temperature and pressure. Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made However, it readily dissolves in most plastics and rubber, and will gradually escape from a container sealed with such materials. Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products ^[111] Xenon is non-toxic, although it does dissolve 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 (see anesthesia subsection above). Toxicity is the degree to which a substance is able to damage an exposed organism The blood-brain barrier (BBB is a metabolic or cellular structure in the Central nervous system (CNS that restricts the passage of various chemical substances and microscopic Anesthesia, or anaesthesia (see spelling differences; from Greek grc αν- an-, "without" and grc αἲσθησις Xenon (ˈzɛnɒn or) is a Chemical element represented by the symbol Xe. Many xenon compounds are explosive and toxic due to their strong oxidative properties. Noble gas compounds are Chemical compounds that include an element from Group 18 Noble gas Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state ^[112]

At 169 m/s, the speed of sound in xenon gas is slower than that in air^[113] (due to the slower average speed of the heavy xenon atoms compared to nitrogen and oxygen molecules), so xenon lowers the resonant frequencies of the vocal tract when inhaled. Sound is a vibration that travels through an elastic medium as a Wave. The vocal tract is that cavity in animals and humans where sound that is produced at the sound source ( Larynx in mammals syrinx in birds is filtered This produces a characteristic lowered voice pitch, opposite the high-pitched voice caused by inhalation of helium. Helium ( He) is a colorless odorless tasteless non-toxic Inert Monatomic Chemical Like helium, xenon does not satisfy the body's need for oxygen and is a simple asphyxiant; consequently, many universities no longer allow the voice stunt as a general chemistry demonstration. As xenon is expensive, the gas sulfur hexafluoride, which is similar to xenon in molecular weight (146 versus 131), is generally used in this stunt, although it too is an asphyxiant. Sulfur hexafluoride is an Inorganic compound with the formula. ^[114]

It is possible to safely breathe heavy gases such as xenon or sulfur hexafluoride when they include a 20% mixture of oxygen (although xenon at this concentration would be expected to produce the unconsciousness of general anesthesia). The lungs mix the gases very effectively and rapidly, so that the heavy gases are purged along with the oxygen and do not accumulate at the bottom of the lungs. ^[115] There is, however, a danger associated with any heavy gas in large quantities: it may sit invisibly in a container, and if a person enters a container filled with an odorless, colorless gas, they may find themselves breathing it unknowingly. Xenon is rarely used in large enough quantities for this to be a concern, though the potential for danger exists any time a tank or container of xenon is kept in an unventilated space. ^[116]

See also

• Penning mixture

References

External links

• WebElements.com – Xenon
• USGS Periodic Table - Xenon
• EnvironmentalChemistry.com - Xenon
• Xenon as an anesthetic

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