Uranium bromides

The trichloride, tnbromide and triiodide of uranium are obtained either by reaction of the elements or by treatment of UH3 with the appropriate halogen acid. The thermal stability of the halides decreases as the atomic number of the halogen increases. No higher uranium bromides or iodides are known. 

BrjOU (s) UOBra (s) Uranium Bromide Oxide BrsOU (s) UOBra (s)... 

Bromides and Iodides. The red-brown tribromide, UBr [13470-19-4], and the black tniodide, Ul [13775-18-3], may both be prepared by direct interaction of the elements, ie, uranium metal with X2 (X = Br, I). The tribromide has also been prepared by interaction of UH and HBr, producing H2 as a reaction product. The tribromide and tniodide complexes are both polymeric soflds with a local bicapped trigonal prismatic coordination geometry. The tribromide is soluble in H2O and decomposes in alcohols. 

Cerous bromide [14457-87-5] CeBr, and praseodymium bromide [13536-53-3] PrBr, are claimed to be suitable for a molten salt bath used for the reduction of uranium oxide by magnesium (16). PrBr is claimed to be alight filter in a cathode ray tube (17). 

The application of the Chelex 100 resin separation and preconcentration, with the direct use of the resin itself as the final sample for analysis, is an extremely useful technique. The elements demonstrated to be analytically determinable from high salinity waters are cobalt, chromium, copper, iron, manganese, molybdenum, nickel, scandium, thorium, uranium, vanadium, and zinc. The determination of chromium and vanadium by this technique offers significant advantages over methods requiring aqueous final forms, in view of their poor elution reproducibility. The removal of sodium, chloride, and bromide allows the determination of elements with short and intermediate half-lives without radiochemistry, and greatly reduces the radiation dose received by personnel. This procedure was successfully applied in a study of... 

In all 28 parameters were individually mapped alkalinity, aluminum, antimony, arsenic, barium, boron, bromide, cadmium, calcium, chloride, chromium, conductivity, copper, fluoride, hardness, iron, lead, magnesium, manganese, nitrate, pH, potassium, selenium, sodium, sulphate, thallium, uranium, and zinc. These parameters constitute the standard inorganic analysis conducted at the DENV Analytical Services Laboratory. 

Bromide analysis, of water, 26 41 Bromide ions, in development solution, 79 205-206 Bromides, 4 319-330 thorium, 24 763 titanium, 25 54 tungsten, 25 379 uranium, 25 439 Bromimide, 4 299, 319 Brominated additive flame retardants, 77 461-468, 471-473t Brominated Anthanthrone Orange, pigment for plastics, 7 367t Brominated aromatic compounds, 7 7 459 Brominated bisphenol A-based epoxy resins, 70 366... 

Heterojunction with intrinsic thin layer (HIT) photovoltaic cell, 23 46-47 Heteroleptic uranium complexes, 25 441 Heterologous promoters, 22 453 Heteronano interface (HNI), 23 838 Heteronium bromide, 4 359t Heteronuclear metal carbonyls, synthesis of, 26 69-71... 

Many uranium(VI) sulfoxide complexes of the type [U02X2(Me2S0)B] (X = anionic ligand) have been synthesized, including chloride, bromide (322, 323), nitrate (41), and acetate (431) adducts. The thiocyanate (113,114) and selenocyanate (292) adducts [U02(XCN)2(Me2SO)2] have been synthesized, and infrared data indicate the presence of O-Me2SO and JV-NCX ligands. 

Major constituents (greater than 5 mg/L) Minor constituents (O.Ol-lO.Omg/L) Selected trace constituents (less than 0.1 mg/L) Bicarbonate, calcium, carbonic acid, chloride, magnesium, silicon, sodium, sulfate Boron, carbonate, fluoride, iron, nitrate, potassium, strontium Aluminum, arsenic, barium, bromide, cadmium, chromium, cobalt, copper, gold, iodide, lead, Uthium, manganese, molybdenum, nickel, phosphate, radium, selenium, silver, tin, titanium, uranium, vanadium, zinc, zirconium... 

Uranium mineral first is digested with hot nitric acid. AH uranium and radium compounds dissolve in the acid. The solution is filtered to separate insoluble residues. The acid extract is then treated with sulfate ions to separate radium sulfate, which is co-precipitated with the sulfates of barium, strontium, calcium, and lead. The precipitate is boiled in an aqueous solution of sodium chloride or sodium hydroxide to form water-soluble salts. The solution is filtered and the residue containing radium is washed with boiling water. This residue also contains sulfates of other alkahne earth metals. The sohd sulfate mixture of radium and other alkahne earth metals is fused with sodium carbonate to convert these metals into carbonates. Treatment with hydrochloric acid converts radium and other carbonates into chlorides, all of which are water-soluble. Radium is separated from this solution as its chloride salt by fractional crystallization. Much of the barium, chemically similar to radium, is removed at this stage. Final separation is carried out by treating radium chloride with hydrobromic acid and isolating the bromide by fractional crystallization. 

Volatile protactinium pentaehloride has been prepared in a vacuum by reaction of the oxide with phosgene at 550° C or with carbon tetrachloride at 200°C. Reduction of this at 600°C with hydrogen leads to protactinium(IV) tetrachloride, Pad. which is isostructural with uranium(IV) tetrachloride, UCI4. The pentaehloride can be converted into the bromide or iodide by heating with the corresponding hydrogen halide or alkali halide... 

RADIUM. [CAS 7440-14-41, Chemical element symbol Ra, at. no. 88, at. wt. 226.025, periodic table group 2 (alkaline earths), mp 700VC, bp 1,140°C, density 5 g/cm3 (20°C). Radium metal is white, rapidly oxidized in air, decomposes H O, and evolves heat continuously at the rate of approximately 0.132 calorie per hour per mg when the decomposition products are retained, and the temperature of radium salts remains about 1,5°C above the surrounding environment. Radium is formed by radioactive transformation of uranium, about 3 million parts of uranium being accompanied in nature by 1 part radium. Radium spontaneously generates radon gas at approximately the rate of 100 mmJ per day per gram of radium, at standard conditions, Radium usually is handled as the chloride or bromide, either as solid or in solution. The radioactivity of the material... 

Notes X = A known adverse effect by an agent CNS = Central nervous system ANS = Autonomic nervous system CV = Cardiovascular system PB = Pyridostigmine bromide OP = Organophosphates CB = Carbamates Pyreth = Pyrethroids Lind = Lindane NA = Nerve agents Mus = Mustard agents Du = Depleted uranium. 

A pure acetonitrile complex of uranium(IV) iodide cannot be isolated,8 but the salt [(CeHj As UI (red) can be readily prepared by the procedure described above in subsection 1, the pure halide being used instead of the acetonitrile complex. f( C H )4NJPaBr6 is extremely soluble in acetonitrile but it can be isolated in 100% yield by room-temperature evaporation of the solvent containing equimolar amounts of the component bromides. 

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