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Rhenium Trioxide Chloride
Rhenium trioxide chloride is an inorganic compound with the formula . It is a colorless, distillable, diamagnetic liquid. It is a rhenium oxychloride. The material is used as a reagent in the preparation of rhenium compounds. Synthesis and reactions Rhenium trioxide chloride can be prepared by chlorination of rhenium trioxide: : With Lewis base A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any sp ...s (L), rhenium trioxide chloride reacts to form adducts with the formula . The compound hydrolyzes readily to give perrhenic acid. Structure The compound adopts a tetrahedral structure with Re-O and Re-Cl bond distances of 1.71 and 2.22 Å. In contrast rhenium trioxide fluoride () is polymeric with octahedral Re centers. References {{Reflist Rhenium compounds Chlorides Transition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Compound
An inorganic compound is typically a chemical compound that lacks carbon–hydrogen bondsthat is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as ''inorganic chemistry''. Inorganic compounds comprise most of the Earth's crust, although the compositions of the deep Mantle (geology), mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include the allotropes of carbon (graphite, diamond, buckminsterfullerene, graphene, etc.), carbon monoxide , carbon dioxide , carbides, and salt (chemistry), salts of inorganic anions such as carbonates, cyanides, cyanates, thiocyanates, isothiocyanates, etc. Many of these are normal parts of mostly organic systems, including organisms; describing a chemical as inorganic does not necessarily mean that it cannot occur within life, living things. History ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamagnetism
Diamagnetism is the property of materials that are repelled by a magnetic field; an applied magnetic field creates an induced magnetic field in them in the opposite direction, causing a repulsive force. In contrast, paramagnetic and ferromagnetic materials are attracted by a magnetic field. Diamagnetism is a quantum mechanical effect that occurs in all materials; when it is the only contribution to the magnetism, the material is called diamagnetic. In paramagnetic and ferromagnetic substances, the weak diamagnetic force is overcome by the attractive force of magnetic dipoles in the material. The Permeability (electromagnetism), magnetic permeability of diamagnetic materials is less than the Vacuum_permeability, permeability of vacuum, ''μ''0. In most materials, diamagnetism is a weak effect which can be detected only by sensitive laboratory instruments, but a superconductivity, superconductor acts as a strong diamagnet because it entirely expels any magnetic field from its inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Oxychloride
Rhenium oxychloride may refer to: *Rhenium oxytetrachloride, , a rhenium(VI) compound *Rhenium trioxide chloride Rhenium trioxide chloride is an inorganic compound with the formula . It is a colorless, distillable, diamagnetic liquid. It is a rhenium oxychloride. The material is used as a reagent in the preparation of rhenium compounds. Synthesis and reac ..., , a rhenium(VII) compound The rhenium oxychlorides are a subset of metal oxyhalides. {{chemistry index Rhenium compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reagent
In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a substance ''consumed'' in the course of a chemical reaction. ''Solvents'', though involved in the reaction mechanism, are usually not called reactants. Similarly, ''catalysts'' are not consumed by the reaction, so they are not reactants. In biochemistry, especially in connection with enzyme-catalyzed reactions, the reactants are commonly called substrates. Definitions Organic chemistry In organic chemistry, the term "reagent" denotes a chemical ingredient (a compound or mixture, typically of inorganic or small organic molecules) introduced to cause the desired transformation of an organic substance. Examples include the Collins reagent, Fenton's reagent, and Grignard reagents. Analytical chemistry In analytical chemistry, a reag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorination Reaction
In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. This kind of conversion is in fact so common that a comprehensive overview is challenging. This article mainly deals with halogenation using elemental halogens (). Halides are also commonly introduced using salts of the halides and halogen acids. Many specialized reagents exist for introducing halogens into diverse substrates, e.g. thionyl chloride. Organic chemistry Several pathways exist for the halogenation of organic compounds, including free radical halogenation, ketone halogenation, electrophilic halogenation, and halogen addition reaction. The nature of the substrate determines the pathway. The facility of halogenation is influenced by the halogen. Fluorine and chlorine are more electrophilic and are more aggressive halogen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Trioxide
Rhenium trioxide or rhenium(VI) oxide is an inorganic compound with the formula ReO3. It is a red solid with a metallic lustre that resembles copper in appearance. It is the only stable trioxide of the Group 7 elements ( Mn, Tc, Re). Preparation and structure Rhenium trioxide can be formed by reducing rhenium(VII) oxide with carbon monoxide at 200 °C or elemental rhenium at 400 °C. :Re2O7 + CO → 2 ReO3 + CO2 :3 Re2O7 + Re → 7 ReO3 Re2O7 can also be reduced with dioxane. Rhenium trioxide crystallizes with a primitive cubic unit cell, with a lattice parameter of 3.742 Å (374.2 pm). The structure of ReO3 is similar to that of perovskite (ABO3), without the large A cation at the centre of the unit cell. Each rhenium center is surrounded by an octahedron defined by six oxygen centers. These octahedra share corners to form the 3-dimensional structure. The coordination number of O is 2, because each oxygen atom has 2 neighbouring Re atoms., p. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lewis Base
A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not involved in bonding but may form a dative bond with a Lewis acid to form a Lewis adduct. For example, NH3 is a Lewis base, because it can donate its lone pair of electrons. Trimethylborane CH3)3Bis a Lewis acid as it is capable of accepting a lone pair. In a Lewis adduct, the Lewis acid and base share an electron pair furnished by the Lewis base, forming a dative bond. In the context of a specific chemical reaction between NH3 and Me3B, a lone pair from NH3 will form a dative bond with the empty orbital of Me3B to form an adduct NH3•BMe3. The terminology refers to the contributions of Gilbert N. Lewis. From p. 142: "We are inclined to think of substances as pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perrhenic Acid
Perrhenic acid is the chemical compound with the formula . It is obtained by evaporating aqueous solutions of . Conventionally, perrhenic acid is considered to have the formula , and a species of this formula forms when rhenium(VII) oxide sublimes in the presence of water or steam. When a solution of is kept for a period of months, it breaks down and crystals of are formed, which contain tetrahedral . For most purposes, perrhenic acid and rhenium(VII) oxide are used interchangeably. Rhenium can be dissolved in nitric or concentrated sulfuric acid to produce perrhenic acid. Properties The structure of solid perrhenic acid is . This species is a rare example of a metal oxide coordinated to water; most often metal–oxo–aquo species are unstable with respect to their corresponding hydroxides: : The two rhenium atoms have different bonding geometries, with one being tetrahedral and the other octahedral, and with the water ligands coordinated to the latter. Gaseous perrhenic acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Trioxide Fluoride
Rhenium trioxide fluoride is an inorganic compound with the formula . It is a white, sublimable, diamagnetic solid, although impure samples appear colored. It one of the few oxyfluorides of rhenium, the other major one being rhenium dioxide trifluoride . The material has no applications, but it is of some academic interest as a rare example of a trioxide fluoride. Synthesis and reactions Rhenium trioxide fluoride can be prepared by fluorination of rhenium trioxide: : With Lewis bases (L) the compound forms adducts with the formula , e.g., L = diethyl ether and acetonitrile. Structure and related compounds According to X-ray crystallography, the compound adopts a helical chain structure featuring octahedral Re centers linked by two fluoride and two oxide bridging ligands. In contrast with , and crystallize with simpler structures. The Mn compound crystallizes as a tetrahedral monomer. The technetium compound crystallizes as dimers with fluoride bridges. Also contrasting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhenium Compounds
Rhenium compounds are compounds formed by the transition metal rhenium (Re). Rhenium can form in many oxidation states, and compounds are known for every oxidation state from −3 to +7 except −2, although the oxidation states +7, +4, and +3 are the most common. Rhenium is most available commercially as salts of perrhenate, including sodium perrhenate, sodium and ammonium perrhenates. These are white, water-soluble compounds. The tetrathioperrhenate anion [ReS4]− is possible. Chalcogenides Oxides Rhenium(IV) oxide (or rhenium dioxide) is an oxide of rhenium, with the chemical formula, formula ReO2. This gray to black crystalline solid is a laboratory reagent that can be used as a catalyst. It adopts the rutile structure. It forms via comproportionation: :2 Re2O7 + 3 Re → 7 ReO2 Single crystals are obtained by chemical transport reaction, chemical transport, using iodine as the transporting agent. At high temperatures it undergoes disproportionation. It forms perr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorides
The term chloride refers to a compound or molecule that contains either a chlorine anion (), which is a negatively charged chlorine atom, or a non-charged chlorine atom covalently bonded to the rest of the molecule by a single bond (). The pronunciation of the word "chloride" is . Chloride salts such as sodium chloride are often soluble in water.Green, John, and Sadru Damji. "Chapter 3." ''Chemistry''. Camberwell, Vic.: IBID, 2001. Print. It is an essential electrolyte located in all body fluids responsible for maintaining acid/base balance, transmitting nerve impulses and regulating liquid flow in and out of cells. Other examples of ionic chlorides include potassium chloride (), calcium chloride (), and ammonium chloride (). Examples of covalent chlorides include methyl chloride (), carbon tetrachloride (), sulfuryl chloride (), and monochloramine (). Electronic properties A chloride ion (diameter 167 pm) is much larger than a chlorine atom (diameter 99 pm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
