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Scandium(III) Nitrate
Scandium(III) nitrate, Sc(NO3)3, is an ionic compound. It is an oxidizer, as all nitrates are. The salt is applied in optical coatings, catalysts, electronic ceramics and the laser industry. Preparation Scandium nitrate can be prepared by the reaction between scandium metal with dinitrogen tetroxide. :Sc + 3 N2O4 → Sc(NO3)3 + 3 NO The anhydrous form can also be obtained by the reaction between scandium chloride and dinitrogen pentoxide. The tetrahydrate can be obtained from the reaction between scandium hydroxide and nitric acid. Properties Scandium nitrate is a white solid which dissolves in water and ethanol. It has multiple hydrated forms, including the dihydrate, trihydrate, and tetrahydrate. The tri- and tetrahydrate exist in the monoclinic crystal system In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium(III) Chloride
Scandium(III) chloride is the inorganic compound with the formula ScCl3. It is a white, high-melting ionic compound, which is deliquescent and highly water-soluble. This salt is mainly of interest in the research laboratory. Both the anhydrous form and hexahydrate (ScCl3•6H2O) are commercially available. Structure ScCl3 crystallises in the layered BiI3 motif, which features octahedral scandium centres. Monomeric ScCl3 is the predominant species in the vapour phase at 900 K, the dimer Sc2Cl6 accounts for approximately 8%.Haaland A., Martinsen K-G, Shorokhov D.J, Girichev G.V., Sokolov V.I, J. Chem. Soc., Dalton Trans., 1998, 2787 - 2792, The electron diffraction spectrum indicates that the monomer is planar and the dimer has two bridging Cl atoms each Sc being 4 coordinate. Reactions ScCl3 is a Lewis acid that absorbs water to give aquo complexes. According to X-ray crystallogrphy, one such hydrate is the salt ''trans''- cCl2(H2O)4l·2H2O. With the less basic ligand t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium(III) Fluoride
Scandium(III) fluoride, ScF3, is an ionic compound. This salt is slightly soluble in water but dissolves in the presence of excess fluoride to form the ScF63− anion. Production ScF3 can be produced by reacting scandium and fluorine.S.A.Cotton, Scandium, Yttrium and the Lanthanides: Inorganic and Coordination Chemistry, Encyclopedia of Inorganic Chemistry, 1994, John Wiley & Sons, . It is also formed during the extraction from the ore thortveitite by the reaction of Sc2O3 with ammonium bifluoride at high temperature:Pradyot Patnaik, 2003, ''Handbook of Inorganic Chemicals'', McGraw-Hill Professional, . : Sc2O3 + 6 NH4HF2 → 2 ScF3 + 6 NH4F + 3 H2O The resulting mixture contains a number of metal fluorides and this is reduced by reaction with calcium metal at high temperature. Further purification steps are required to produce usable metallic scandium. Properties Scandium trifluoride exhibits the unusual property of negative thermal expansion, meaning it shrinks when heated. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidizer
An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxidizer is any substance that oxidizes another substance. The oxidation state, which describes the degree of loss of electrons, of the oxidizer decreases while that of the reductant increases; this is expressed by saying that oxidizers "undergo reduction" and "are reduced" while reducers "undergo oxidation" and "are oxidized". Common oxidizing agents are oxygen, hydrogen peroxide and the halogens. In one sense, an oxidizing agent is a chemical species that undergoes a chemical reaction in which it gains one or more electrons. In that sense, it is one component in an oxidation–reduction (redox) reaction. In the second sense, an oxidizing agent is a chemical species that transfers electronegative atoms, usually oxygen, to a substrate. Combust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrates
Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. Structure The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1. This charge results from a combination formal charge in which each of the three oxygens carries a − charge, whereas the nitrogen carries a +1 charge, all these adding up to formal charge of the polyatomic nitrate ion. This arrangement is commonly used as an example of resonance. Like the isoelectronic carbonate ion, the nitrate ion can be represented by resonance structures: Dietary nitrate A rich source of inorganic nitrate in the human diets come from leafy green foods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium
Scandium is a chemical element with the symbol Sc and atomic number 21. It is a silvery-white metallic d-block element. Historically, it has been classified as a rare-earth element, together with yttrium and the Lanthanides. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia. Scandium is present in most of the deposits of rare-earth and uranium compounds, but it is extracted from these ores in only a few mines worldwide. Because of the low availability and difficulties in the preparation of metallic scandium, which was first done in 1937, applications for scandium were not developed until the 1970s, when the positive effects of scandium on aluminium alloys were discovered, and its use in such alloys remains its only major application. The global trade of scandium oxide is 15–20 tonnes per year. The properties of scandium compounds are intermediate between those of aluminium and yttrium. A diagonal relationship exists betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinitrogen Tetroxide
Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russia rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium mixture with nitrogen dioxide. Its molar mass is 92.011 g/mol. Dinitrogen tetroxide is a powerful oxidizer that is hypergolic (spontaneously reacts) upon contact with various forms of hydrazine, which has made the pair a common bipropellant for rockets. Structure and properties Dinitrogen tetroxide could be regarded as two nitro groups (-NO2) bonded together. It forms an equilibrium mixture with nitrogen dioxide. The molecule is planar with an N-N bond distance of 1.78Å and N-O distances of 1.19Å. The N-N distance corresponds to a weak bond, since it is significantly longer than the average N-N single bond length of 1.45Å. This exceptionally weak σ bond (amounting to overlapping of the ''sp''2 hybrid orbitals of the two NO2 units) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anhydrous
A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achieve perfect dryness; anhydrous compounds gradually absorb water from the atmosphere so they must be stored carefully. Solids Many salts and solids can be dried using heat, or under vacuum. Desiccators can also be used to store reagents in dry conditions. Common desiccants include phosphorus pentoxide and silica gel. Chemists may also require dry glassware for sensitive reactions. This can be achieved by drying glassware in an oven, by flame, or under vacuum. Dry solids can be produced by freeze-drying, which is also known as lyophilization. Liquids or solvents In many cases, the presence of water can prevent a reaction from happening, or cause undesirable products to form. To prevent this, anhydrous solvents must be used when performi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium Chloride
Scandium(III) chloride is the inorganic compound with the formula ScCl3. It is a white, high-melting ionic compound, which is deliquescent and highly water-soluble. This salt is mainly of interest in the research laboratory. Both the anhydrous form and hexahydrate (ScCl3•6H2O) are commercially available. Structure ScCl3 crystallises in the layered BiI3 motif, which features octahedral scandium centres. Monomeric ScCl3 is the predominant species in the vapour phase at 900 K, the dimer Sc2Cl6 accounts for approximately 8%.Haaland A., Martinsen K-G, Shorokhov D.J, Girichev G.V., Sokolov V.I, J. Chem. Soc., Dalton Trans., 1998, 2787 - 2792, The electron diffraction spectrum indicates that the monomer is planar and the dimer has two bridging Cl atoms each Sc being 4 coordinate. Reactions ScCl3 is a Lewis acid that absorbs water to give aquo complexes. According to X-ray crystallogrphy, one such hydrate is the salt ''trans''- cCl2(H2O)4l·2H2O. With the less basic ligand tetra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinitrogen Pentoxide
Dinitrogen pentoxide is the chemical compound with the formula , also known as nitrogen pentoxide or nitric anhydride. It is one of the binary nitrogen oxides, a family of compounds that only contain nitrogen and oxygen. It exists as colourless crystals that melt at 41 °C. Its boiling point is 47 °C, and sublimes slightly above room temperature, yielding a colorless gas.Peter Steele Connell The Photochemistry of Dinitrogen Pentoxide'. Ph. D. thesis, Lawrence Berkeley National Laboratory. Dinitrogen pentoxide is an unstable and potentially dangerous oxidizer that once was used as a reagent when dissolved in chloroform for nitrations but has largely been superseded by nitronium tetrafluoroborate (). is a rare example of a compound that adopts two structures depending on the conditions. The solid is a salt, nitronium nitrate, consisting of separate nitronium cations and nitrate anions ; but in the gas phase and under some other conditions it is a covalently-bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium Hydroxide
Scandium(III) hydroxide is an inorganic compound with the chemical formula Sc(OH)3, the trivalent hydroxide of scandium. It is an amphoteric In chemistry, an amphoteric compound () is a molecule or ion that can react both as an acid and as a base. What exactly this can mean depends on which definitions of acids and bases are being used. One type of amphoteric species are amphipro ... compound. It is slightly soluble in water, and its saturated solution (pH = 7.85) contains Sc(OH)3 and a small amount of Sc(OH)2+. The solubility of scandium(III) hydroxide in water is 0.0279 mol/L. It will convert to ScO(OH) after aging, greatly reducing the solubility (0.0008 mol/L). Scandium(III) hydroxide can be produced by reacting scandium salts and alkali hydroxides. In the reaction, different starting ingredients can generate different intermediates such as Sc(OH)1.75Cl1.25, Sc(OH)2NO3 and Sc(OH)2.32(SO4)0.34.Mironov, N. N.; Mal'kevich, N. V. Scandium hydroxide formation react ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as pigments in inks and dyes. Nitric acid is also commonly used as a strong oxidizing agen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a Volatility (chemistry), volatile, Combustibility and flammability, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of Carbohydrate, sugars by yeasts or via Petrochemistry, petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the Chemical synthesis, synthesis of organic compounds, and as a Alcohol fuel, fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
