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Xenon Dibromide
Xenon dibromide is an unstable chemical compound with the chemical formula XeBr2. It was only produced by the decomposition of iodine-129: :129IBr2– → XeBr2 + e– Attempts to prepare this compound by combining elemental xenon and bromine only resulted in the XeBr radical. This compound is expected to be less stable than xenon difluoride Xenon difluoride is a powerful fluorinating agent with the chemical formula , and one of the most stable xenon compounds. Like most covalent inorganic fluorides it is moisture-sensitive. It decomposes on contact with water vapor, but is otherwis ... and xenon dichloride. It is also expected to decompose to xenon and bromine. References {{Bromides Xenon(II) compounds Bromides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Journal Of Physical Chemistry A
''The Journal of Physical Chemistry A'' is a scientific journal which reports research on the chemistry of molecules - including their dynamics, spectroscopy, kinetics, structure, bonding, and quantum chemistry. It is published weekly by the American Chemical Society. Before 1997 the title was simply ''Journal of Physical Chemistry''. Owing to the ever-growing amount of research in the area, in 1997 the journal was split into ''Journal of Physical Chemistry A'' (molecular theoretical and experimental physical chemistry) and '' The Journal of Physical Chemistry B'' (solid state, soft matter, liquids, etc.). Beginning in 2007, the latter underwent a further split, with '' The Journal of Physical Chemistry C'' now being dedicated to nanotechnology, molecular electronics, and related subjects. Editors-in-chief *1896–1932 Wilder Dwight Bancroft, Joseph E. Trevor *1933–1951 S. C. Lind *1952–1964 William A. Noyes *1965–1969 F. T. Wall *1970–1980 Bryce Crawford *1980â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Difluoride
Xenon difluoride is a powerful fluorinating agent with the chemical formula , and one of the most stable xenon compounds. Like most covalent inorganic fluorides it is moisture-sensitive. It decomposes on contact with water vapor, but is otherwise stable in storage. Xenon difluoride is a dense, colourless crystalline solid. It has a nauseating odour and low vapor pressure. Structure Xenon difluoride is a linear molecule with an Xe–F bond length of in the vapor stage, and 200 pm in the solid phase. The packing arrangement in solid shows that the fluorine atoms of neighbouring molecules avoid the equatorial region of each molecule. This agrees with the prediction of VSEPR theory, which predicts that there are 3 pairs of non-bonding electrons around the equatorial region of the xenon atom. At high pressures, novel, non-molecular forms of xenon difluoride can be obtained. Under a pressure of ~50 GPa, transforms into a semiconductor consisting of units linked in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Dichloride
Xenon dichloride (XeCl2) is a xenon compound and the only known stable chloride of xenon. The compound can be prepared by using microwave discharges towards the mixture of xenon and chlorine, and it can be isolated from a condensate trap. One experiment tried to use xenon, chlorine and boron trichloride to produce XeCl2·BCl3, but only generated xenon dichloride. However, it is still doubtful whether xenon dichloride is a true compound or a Van der Waals molecule A Van der Waals molecule is a weakly bound complex of atoms or molecules held together by intermolecular attractions such as Van der Waals forces or by hydrogen bonds. The name originated in the beginning of the 1970s when stable molecular clust ... composed of a xenon atom and a chlorine molecule connected by a secondary bond. References Xenon(II) compounds Chlorides Nonmetal halides Van der Waals molecules {{Inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine-129
Iodine-129 (129I) is a long-lived radioisotope of iodine which occurs naturally, but also is of special interest in the monitoring and effects of man-made nuclear fission products, where it serves as both tracer and potential radiological contaminant. Formation and decay 129I is one of seven long-lived fission products. It is primarily formed from the fission of uranium and plutonium in nuclear reactors. Significant amounts were released into the atmosphere as a result of nuclear weapons testing in the 1950s and 1960s. It is also naturally produced in small quantities, due to the spontaneous fission of natural uranium, by cosmic ray spallation of trace levels of xenon in the atmosphere, and by cosmic ray muons striking tellurium-130. 129I decays with a half-life of 15.7 million years, with low-energy beta and gamma emissions, to stable xenon-129 (129Xe). Fission product 129I is one of the seven long-lived fission products that are produced in significant amounts. Its yield is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neil Bartlett (chemist)
Neil Bartlett (15 September 1932 – 5 August 2008) was a chemist who specialized in fluorine and compounds containing fluorine, and became famous for creating the first noble gas compounds. He taught chemistry at the University of British Columbia and the University of California, Berkeley. Biography Neil Bartlett was born on 15 September 1932 in Newcastle-upon-Tyne, England. Bartlett's interest in chemistry dated back to an experiment at Heaton Grammar School when he was only eleven years old, in which he prepared "beautiful, well-formed" crystals by reaction of aqueous ammonia with copper sulfate. He explored chemistry by constructing a makeshift lab in his parents' home using chemicals and glassware he purchased from a local supply store. He went on to attend King's College, University of Durham (which went on to become Newcastle University) in the United Kingdom where he obtained a Bachelor of Science (1954) and then a doctorate (1958). In 1958, Bartlett's career began ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon
Xenon is a chemical element with the symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized. Xenon is used in flash lamps and arc lamps, and as a general anesthetic. The first excimer laser design used a xenon dimer molecule (Xe2) as the lasing medium, and the earliest laser designs used xenon flash lamps as pumps. Xenon is also used to search for hypothetical weakly interacting massive particles and as a propellant for ion thrusters in spacecraft. Naturally occurring xenon consists of seven stable isotopes and two long-lived radioactive isotopes. More than 40 unstable xenon isotopes undergo radioactive decay, and the isotope ratios of xenon are an important tool for studying the early history of the Solar System. Radioactive xenon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromine
Bromine is a chemical element with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table ( halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived from the Ancient Greek (bromos) meaning "stench", referring to its sharp and pungent smell. Elemental bromine is very reactive and thus does not occur as a native element in nature but it occurs in colourless soluble crystalline mineral halide salts, analogous to table salt. In fact, bromine and all the halogens are so reactive that they form bonds in pairs—never in single atoms. While it is rather rare in the Earth's crust, the high solubility of the bromide ion (Br) has caused its accumulation in the oceans. Comme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radical (chemistry)
In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes. A notable example of a radical is the hydroxyl radical (HO·), a molecule that has one unpaired electron on the oxygen atom. Two other examples are triplet oxygen and triplet carbene (꞉) which have two unpaired electrons. Radicals may be generated in a number of ways, but typical methods involve redox reactions. Ionizing radiation, heat, electrical discharges, and electrolysis are known to produce radicals. Radicals are intermediates in many chemical reactions, more so than is apparent from the balanced equations. Radicals are important in combustion, atmospheric chemistry, polymerization, plasma chemistry, biochemistry, and many other chemical processes. A majority ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Difluoride
Xenon difluoride is a powerful fluorinating agent with the chemical formula , and one of the most stable xenon compounds. Like most covalent inorganic fluorides it is moisture-sensitive. It decomposes on contact with water vapor, but is otherwise stable in storage. Xenon difluoride is a dense, colourless crystalline solid. It has a nauseating odour and low vapor pressure. Structure Xenon difluoride is a linear molecule with an Xe–F bond length of in the vapor stage, and 200 pm in the solid phase. The packing arrangement in solid shows that the fluorine atoms of neighbouring molecules avoid the equatorial region of each molecule. This agrees with the prediction of VSEPR theory, which predicts that there are 3 pairs of non-bonding electrons around the equatorial region of the xenon atom. At high pressures, novel, non-molecular forms of xenon difluoride can be obtained. Under a pressure of ~50 GPa, transforms into a semiconductor consisting of units linked in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Dichloride
Xenon dichloride (XeCl2) is a xenon compound and the only known stable chloride of xenon. The compound can be prepared by using microwave discharges towards the mixture of xenon and chlorine, and it can be isolated from a condensate trap. One experiment tried to use xenon, chlorine and boron trichloride to produce XeCl2·BCl3, but only generated xenon dichloride. However, it is still doubtful whether xenon dichloride is a true compound or a Van der Waals molecule A Van der Waals molecule is a weakly bound complex of atoms or molecules held together by intermolecular attractions such as Van der Waals forces or by hydrogen bonds. The name originated in the beginning of the 1970s when stable molecular clust ... composed of a xenon atom and a chlorine molecule connected by a secondary bond. References Xenon(II) compounds Chlorides Nonmetal halides Van der Waals molecules {{Inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon(II) Compounds
Xenon is a chemical element with the Symbol (chemistry), symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Atmosphere of Earth, Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized. Xenon is used in Flashtube#Xenon, flash lamps and xenon arc lamp, arc lamps, and as a general anaesthesia, general anesthetic. The first excimer laser design used a xenon Dimer (chemistry), dimer molecule (Xe2) as the Active laser medium, lasing medium, and the earliest laser designs used xenon flash lamps as Laser pumping, pumps. Xenon is also used to search for hypothetical weakly interacting massive particles and as a propellant for ion thrusters in spacecraft. Naturally occurring xenon consists of Isotopes of xenon, seven stable isotopes and two long-lived radioactive isotopes. More than 40 unstable xenon iso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
