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Protactinyl Nitrate
Protactinyl nitrate, protactinium(V) oxynitrate, or erroneously known as protactinium nitrate, is a radioactive chemical compound with the formula PaO(NO3)3·''x''H2O (1.5 ≤ ''x'' ≤ 4). It is a white solid that readily hydrolyzes to protactinium(V) oxide in moist air. This compound is a common commercial source of protactinium. Preparation and decomposition Protactinyl nitrate was first prepared in 1966 by reacting protactinium(V) chloride or protactinium(V) bromide with fuming nitric acid Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most com .... Lower concentrations of nitric acid cannot be used, due to the hydrolysis of the compound. Protactinyl nitrate decomposes at 400 °C to protactinium(V) oxide. References {{Nitrates Protactinium compounds Nitrates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, 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 synthetic dyes and medicines (e.g. metronidazole). Nitric acid is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranyl Nitrate
Uranyl nitrate is a water-soluble yellow uranium salt with the formula . The hexa-, tri-, and dihydrates are known. The compound is mainly of interest because it is an intermediate in the preparation of nuclear fuels. In the nuclear industry, it is commonly referred to as yellow salt. Uranyl nitrate can be prepared by reaction of uranium salts with nitric acid. It is soluble in water, ethanol, and acetone. As determined by neutron diffraction, the uranyl center is characteristically linear with short U=O distances. In the equatorial plane of the complex are six U-O bonds to bidentate nitrate and two water ligands. At 245 pm, these U-O bonds are much longer than the U=O bonds of the uranyl center. Uses Processing of nuclear fuels Uranyl nitrate is important for nuclear reprocessing. It is the compound of uranium that results from dissolving the decladded spent nuclear fuel rods or yellowcake in nitric acid, for further separation and preparation of uranium hexafluoride for i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protactinium(V) Oxide
Protactinium(V) oxide is a chemical compound with the formula Pa2 O5. When it is reduced with hydrogen, it forms PaO2. Aristid V. Grosse was first to prepare 2 mg of Pa2O5 in 1927. Pa2O5 does not dissolve in concentrated HNO3, but dissolves in HF and in a HF + H2SO4 mixture and reacts at high temperatures with solid oxides of alkali metal and alkaline earth metals.Boris F. Myasoedov, H. W. Kirby, & Ivan G. Tananaev (2006) Protactinium, Chapter 4 in Morss, Lester R. & Edelstein, Norman M. & Fuger, Jean, (edit.The Chemistry of the Actinide and Transactinide Elements (PDF) (3. painos). Dordrecht: Springer. ss. 161–252. As protactinium(V) oxide, like other protactinium compounds, is radioactive, toxic and very rare, it has very limited technological use. Mixed oxides of Nb, Mg, Ga and Mn, doped with 0.005–0.52% Pa2O5, have been used as high temperature dielectric In electromagnetism, a dielectric (or dielectric medium) is an Insulator (electricity), electrical insulato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protactinium(V) Chloride
Protactinium(V) chloride is the chemical compound composed of protactinium and chlorine with the formula PaCl5. It forms yellow monoclinic crystals and has a unique structure composed of chains of 7 coordinate, pentagonal bipyramidal, protactinium atoms sharing edges.R. P. Dodge, G. S. Smith, Q. Johnson, R. E. Elson: „The Crystal Structure of Protactinium Pentachloride“, '' Acta Crystallogr.'', 1967, ''22'', 85–89; . Protactinium(V) chloride can react with boron tribromide at high temperatures to form protactinium(V) bromide.Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6, S. 1177. It also reacts with fluorine Fluorine is a chemical element; it has Chemical symbol, symbol F and atomic number 9. It is the lightest halogen and exists at Standard temperature and pressure, standard conditions as pale yellow Diatomic m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protactinium(V) Bromide
Protactinium(V) bromide is an inorganic compound. It is a halide of protactinium, consisting of protactinium and bromine. It is radioactive and has a chemical formula of PaBr5, which is a red crystal of the monoclinic crystal system. Preparation Protactinium(V) bromide can be obtained by reacting protactinium(V) chloride with boron tribromide at 500 to 550 °C.Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6, S. 1177. :3PaCl5 + 5BBr3 → 3PaBr5 + 5BCl3 It can also be obtained by reacting protactinium(V) oxide with aluminum bromide at 400 °C. Physical properties Protactinium(V) bromide is an orange-red, crystalline, extremely moisture-sensitive solid that reacts violently with water and ammonia, but is persistent in absolutely dry air. It is insoluble in isopentane, dichloromethane and benzene, and in anhyd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protactinium Compounds
Protactinium compounds are compounds containing the element protactinium (symbol: Pa). These compounds usually have protactinium in the +5 oxidation state, although these compounds can also exist in the +2, +3 and +4 oxidation states. Properties of protactinium compounds Here ''a'', ''b'' and ''c'' are lattice constants in picometers, No is space group number and ''Z'' is the number of formula units per unit cell; ''fcc'' stands for the Cubic crystal system, face-centered cubic symmetry. Density was not measured directly but calculated from the lattice parameters. Oxides and oxygen-containing salts Protactinium oxides are known for the metal oxidation states +2, +4 and +5. The most stable is white pentoxide Protactinium(V) oxide, Pa2O5, which can be produced by igniting protactinium(V) hydroxide in air at a temperature of 500 °C.#Greenwood, Greenwood, p. 1268 Its crystal structure is cubic, and the chemical composition is often non-stoichiometric, described as PaO2.2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
