Rubidium bromide fluoride

Since the sum of the ionic radii is known (from x-ray studies), both radii may then be evaluated. Similarly, if the S values for the argon, krypton, and xenon structures are known, the interionic distances in KC1, RbBr, and Csl may be used to calculate ionic radii for K+, Rb+, Cs4, Cl, Br, and I . The values for cesium and iodide ions must be regarded cautiously (for, as we shall see presently, the structure of the cesium halides is different from that of the other alkali halides) but the radii of the retnaining ions fit into a self-consistent system. Thus, adding from sodium fluoride (0.95 k) to R Br from rubidium bromide (1.95 A) yields a sum not greatly different from the observed interionic distance in solid sodium bromide (2.98 A). 

Clusius K, Goldmann J, Perlick A (1949) Low- temperature research. VII. The specific heat of the alkali halides lithium fluoride, sodium chloride, potassium chloride, potassium bromide, potassium iodide, rubidium bromide, and rubidium iodide between 10° and 273° abs. Z Naturforsch 4a 424—432... 

Rubidium metal alloys with the other alkaU metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double haUde salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and 2iac. These complexes are generally water iasoluble and not hygroscopic. The soluble mbidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide. 

IONIC CRYSTAL. A crystal ihut consists effectively of ions bound lugclher by Iheir electrostatic attraction. Examples of such crystals are the alkali halides, including potassium fluoride, potassium chloride, potassium bromide, potassium iodide, sodium fluoride, and the other combinations of sodium, cesium, rubidium or lithium ions with fluoride, chloride, bromide or iodide ions. Many other types of ionic crystals are known,... 

H. Stamm also measured the solubilities of the salts of the alkalies in liquid ammonia —potassium hydroxide, nitrate, sulphate, chromate, oxalate, perchlorate, persulphate, chloride, bromide, iodide, carbonate, and chlorate rubidium chloride, bromide, and sulphate esesium chloride, iodide, carbonate, and sulphate lithium chloride and sulphate sodium phosphate, phosphite, hypophosphite, fluoride, chloride, iodide, bromate, perchlorate, periodate, hyponitrire, nitrite, nitrate, azide, dithionate, chromate, carbonate, oxalate, benzoate, phtnalate, isophthalate ammonium, chloride, chlorate, bromide, iodide, perchlorate, sulphate, sulphite, chromate, molybdate, nitrate, dithionate, thiosulphate, persulphate, thiocyanate, phosphate, phosphite, hypophosphite, arsenate, arsenite, amidosulphonate, ferrocyanide, carbonate, benzoate, methionate, phenylacetate, picrate, salicylate, phenylpropionate, benzoldisulphonate, benzolsulphonate, phthalate, trimesmate, mellitate, aliphatic dicarboxylates, tartrate, fumarate, and maleinate and phenol. 

The Equation of State of the Alkali Halides.—The alkali halides, the fluorides, chlorides, bromides, and iodides of lithium, sodium, potassium, rubidium, and caesium have been more extensively studied experimentally than any other group of ionic crystals. For most of these materials, enough data are available to make a fairly satisfactory comparison between experiment and theory. The observations include the compressibility and its change with pressure, at room temperature, from which the quantities ai(T), o2(r) of Eq. (1.1), Chap. XIII, can be found... 

The structure of sodium chloride, which is the prototype for most of the alkali halides, is best described as a cubic closest packed array of Cl- ions with the Na+ ions in all of the octahedral holes [see Fig. 16.42(b)]. The relative sizes of these ions are such that rua 0.66i ci-> so this solid obeys the guidelines given previously. Note that the CP ions are forced apart by the Na+ ions, which are too large for the octahedral holes in the closest packed array of CP ions. Since the number of octahedral holes is the same as the number of packed spheres, all the octahedral holes must be filled with Na+ ions to achieve the required 1 1 stoichiometry. Most other alkali halides also have the sodium chloride structure. In fact, all the halides of lithium, sodium, potassium, and rubidium have this structure. Cesium fluoride has the sodium chloride structure but because of the large size of Cs+ ions, in this case the Cs ions form a cubic closest packed arrangement with the F ions in all the octahedral holes. On the other hand, cesium chloride, in which the Cs+ and CP ions are almost the same size, has a simple cubic structure of CP ions, with each Cs+ ion in the cubic hole in the center of each cube. The compounds cesium bromide and cesium iodide also have this latter structure. 

More and more, however, other solvents are coming into use in the laboratory and in industry. Aside from organic solvents such as alcohols, acetone, and hydrocarbons, which have been in use for many years, industrial processes use such solvents as sulfuric acid, hydrogen fluoride, ammonia, molten sodium hexafluoroaluminate (cryolite), various other ionic liquids (Welton, 1999), and liqnid metals, lander and Lafrenz (1970) cite the industrial use of bromine to separate caesium bromide (sol y 19.3g/100g bromine) from the much less soluble rubidium salt. The list of solvents available for preparative and analytical purposes in the laboratory now is long and growing, and though water will still be the first solvent that comes to mind, there is no reason to stop there. 

Hydrogen bromide Hydrogen chloride Hydrogen fluoride Indium hydride Rubidium hydride Stibine... 

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