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Xenon Oxydifluoride
Xenon oxydifluoride is an inorganic compound with the molecular formula XeOF2. The first definitive isolation of the compound was published on 3 March 2007, producing it by the previously-examined route of partial hydrolysis of xenon tetrafluoride. : The compound has a T-shaped geometry and does not form polymers, though it does form an adduct with acetonitrile and with hydrogen fluoride. Although stable at low temperatures, it rapidly decomposes upon warming, either by losing the oxygen atom or by disproportionating into 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 otherw ... and xenon dioxydifluoride: : : References {{Fluorine compounds Xenon(IV) compounds Oxyfluorides Substances discovered in the 2000s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T-shaped Molecular Geometry
In chemistry, T-shaped molecular geometry describes the structures of some molecules where a central atom has three ligands. Ordinarily, three-coordinated compounds adopt trigonal planar or pyramidal geometries. Examples of T-shaped molecules are the halogen trifluorides, such as ClF3. According to VSEPR theory, T-shaped geometry results when three ligands and two lone pairs of electrons are bonded to the central atom, written in AXE notation as AX3E2. The T-shaped geometry is related to the trigonal bipyramidal molecular geometry for AX5 molecules with three equatorial and two axial ligands. In an AX3E2 molecule, the two lone pairs occupy two equatorial positions, and the three ligand atoms occupy the two axial positions as well as one equatorial position. The three atoms bond at 90° angles on one side of the central atom, producing the T shape. The trifluoroxenate(II) anion, , has been investigated as a possible first example of an AX3E3 molecule, which might be expected by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Oxytetrafluoride
Xenon oxytetrafluoride () is an inorganic chemical compound. It is a colorless stable liquid with a melting point of that can be synthesized by partial hydrolysis of , or the reaction of with silica or : : + → + + A high-yield synthesis proceeds by the reaction of with at . As are most xenon oxides, it is extremely reactive and unstable, and hydrolyses in water to give dangerously hazardous and corrosive products, including hydrogen fluoride: :2 + 4 → 2 + 8 + 3 In addition, some ozone Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the l ... and fluorine is formed. Reactions reacts with in the following steps: : + → + 2 : + → + 2 The formed is a dangerous explosive, decomposing explosively to Xe and : :2 → 2 + 3 In its liquid form, exhibits amphoteric be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Dioxydifluoride
Xenon dioxydifluoride is an inorganic chemical compound with the formula XeO2F2. At room temperature it exists as a metastable solid, which decomposes slowly into xenon difluoride, but the cause of this decomposition is unknown. Preparation Xenon dioxydifluoride is prepared by reacting xenon trioxide with xenon oxytetrafluoride Xenon oxytetrafluoride () is an inorganic chemical compound. It is a colorless stable liquid with a melting point of that can be synthesized by partial hydrolysis of , or the reaction of with silica or : : + → + + A high-yield synthesi .... : XeO3 + XeOF4 -> 2XeO2F2 References {{Inorganic-stub Nonmetal halides Oxyfluorides Xenon(VI) compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the substance and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Tetrafluoride
Xenon tetrafluoride is a chemical compound with chemical formula . It was the first discovered binary compound of a noble gas. It is produced by the chemical reaction of xenon with fluorine: : Xe + 2 → This reaction is exothermic, releasing an energy of 251 kJ/mol. Xenon tetrafluoride is a colorless crystalline solid that sublimes at 117 °C. Its structure was determined by both NMR spectroscopy and X-ray crystallography in 1963. The structure is square planar, as has been confirmed by neutron diffraction studies. According to VSEPR theory, in addition to four fluoride ligands, the xenon center has two lone pairs of electrons. These lone pairs are mutually ''trans''. Synthesis Xenon tetrafluoride is produced by heating a mixture of xenon and fluorine in a 1:5 molar ratio in a nickel container to 400 °C. Some xenon difluoride () and xenon hexafluoride () is also produced, where increased temperature or decreased fluorine concentration in the input ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer
A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adduct
An adduct (from the Latin ''adductus'', "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all components. The resultant is considered a distinct molecular species. Examples include the addition of sodium bisulfite to an aldehyde to give a sulfonate. It can just be considered as a single product resulting from the direct combination of different molecules which comprises all the reactant molecules' atoms. Adducts often form between Lewis acids and Lewis bases. A good example is the formation of adducts between the Lewis acid borane and the oxygen atom in the Lewis bases, tetrahydrofuran (THF): BH3·O(CH2)4 or diethyl ether: BH3·O(CH3CH2)2. Many Lewis acids and Lewis bases reacting in the gas phase or in non-aqueous solvents to form adducts have been examined in the ECW model. Trimethylboron, trimethyltin chloride and bis(hexaflu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetonitrile
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile (hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic). It is produced mainly as a byproduct of acrylonitrile manufacture. It is used as a polar aprotic solvent in organic synthesis and in the purification of butadiene. The skeleton is linear with a short distance of 1.16 Å. Acetonitrile was first prepared in 1847 by the French chemist Jean-Baptiste Dumas. Applications Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower. Heat is then employed in the separatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Fluoride
Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula . This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid. It is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers, e.g. polytetrafluoroethylene (PTFE). HF is widely used in the petrochemical industry as a component of superacids. Hydrogen fluoride boils at near room temperature, much higher than other hydrogen halides. Hydrogen fluoride is an extremely dangerous gas, forming corrosive and penetrating hydrofluoric acid upon contact with moisture. The gas can also cause blindness by rapid destruction of the corneas. History In 1771 Carl Wilhelm Scheele prepared the aqueous solution, hydrofluoric acid in large quantities, although hydrofluoric acid had been known in the glass industry before then. French chemist Edmond Frémy (1814–1894) is credited with discoveri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disproportionation
In chemistry, disproportionation, sometimes called dismutation, is a redox reaction in which one compound of intermediate oxidation state converts to two compounds, one of higher and one of lower oxidation states. More generally, the term can be applied to any desymmetrizing reaction of the following type, regardless of whether it is a redox or some other type of process: :2A -> A' + A'' Examples *Mercury(I) chloride disproportionates upon UV-irradiation: :Hg2Cl2 → Hg + HgCl2 *Phosphorous acid disproportionates upon heating to give phosphoric acid and phosphine: :4 → 3 H3PO4 + PH3 *Desymmetrizing reactions are sometimes referred to as disproportionation, as illustrated by the thermal degradation of bicarbonate: :2 → + H2CO3 :The oxidation numbers remain constant in this acid-base reaction. This process is also called autoionization. *Another variant on disproportionation is radical disproportionation, in which two radicals form an alkene and an alkane. : Reverse r ... [...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 Grading in education is the process of applying standardized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenon Dioxydifluoride
Xenon dioxydifluoride is an inorganic chemical compound with the formula XeO2F2. At room temperature it exists as a metastable solid, which decomposes slowly into xenon difluoride, but the cause of this decomposition is unknown. Preparation Xenon dioxydifluoride is prepared by reacting xenon trioxide with xenon oxytetrafluoride Xenon oxytetrafluoride () is an inorganic chemical compound. It is a colorless stable liquid with a melting point of that can be synthesized by partial hydrolysis of , or the reaction of with silica or : : + → + + A high-yield synthesi .... : XeO3 + XeOF4 -> 2XeO2F2 References {{Inorganic-stub Nonmetal halides Oxyfluorides Xenon(VI) compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
