Rubidium chloride

Rubidium can be liquid at room temperature. It is a soft, silvery-white metallic element of the alkali group and is the second most electropositive and alkaline element. It ignites spontaneously in air and reacts violently in water, setting fire to the liberated hydrogen. As with other alkali metals, it forms amalgams with mercury and it alloys with gold, cesium, sodium, and potassium. It colors a flame yellowish violet. Rubidium metal can be prepared by reducing rubidium chloride with calcium, and by a number of other methods. It must be kept under a dry mineral oil or in a vacuum or inert atmosphere. 

Rubidium-alaun, m. rubidium alum, -chlorid, n. rubidium chloride, -jodid, n. rubidium iodide, -oxydhydrat, n. rubidium hydroxide, -platinchlorid, n. rubidium chloroplatinate. 

Explain why the lattice energy of lithium chloride (861 kj-mol ) is greater than that of rubidium chloride (695 kj-mol ), given that they have similar arrangements of ions in the crystal lattice. See Appendix 2D. 

Reduction of the chlorides by Ba, Na or Ca is a satisfactory method of preparing small amounts of pure Rb and Cs. Rubidium chloride is dissolved in barium azide aq sol and evaporated at 25°C to dryness. The intimate mixture is then heated under vacuum. The BafNjIj decomposes at ca. 100-200°C to Ba metal, which reduces RbCI to Rb this distills at temperatures low enough to prevent contamination by Ba vapor. The most widely employed method uses Ca as the reducing agent ... 

Preparation. It is made by the reaction of metallic sodium with hot molten rubidium chloride. 

RbCl RUBIDIUM CHLORIDE 95.4464 -1.6358E+04 -2.8542E+01 6.6137E-03... 

Rubidium does not exist in its elemental metallic form in nature. However, in compound forms it is the 22nd most abundant element on Earth and, widespread over most land areas in mineral forms, is found in 310 ppm. Seawater contains only about 0.2 ppm of rubidium, which is a similar concentration to lithium. Rubidium is found in complex minerals and until recently was thought to be a rare metal. Rubidium is usually found combined with other Earth metals in several ores. The lepidolite (an ore of potassium-lithium-aluminum, with traces of rubidium) is treated with hydrochloric acid (HCl) at a high temperature, resulting in lithium chloride that is removed, leaving a residue containing about 25% rubidium. Another process uses thermochemical reductions of lithium and cesium ores that contain small amounts of rubidium chloride and then separate the metals by fractional distillation. 

Rubidium chloride is used for the production of rubidium metal, which, in the liquid form, has a high heat transfer coefflcient, making it useful as a coolant (along with other alkali metals) for nuclear reactors. 

Rubidium chlorides (RbCl) is a source of rubidium metal and is used as a chemical reagent. 

Cesium chlorostannate, Cs2SnCl6, more insoluble than the rubidium salt, precipitates before any rubidium starts to precipitate. Under such controlled addition of stannic chloride, potassium chloride remains in solution in chloride form. Rubidium chlorostannate complex, on thermal decomposition, forms rubidium chloride, RbCl. 

Rubidium chloride is used in preparing rubidium metal and many rubidium salts. Also, it is used in pharmaceuticals as an antidepressant and as a density-gradient medium for centrifugal separation of viruses, DNA, and large particles. Other applications are as an additive to gasoline to improve its octane number and as a catalyst. 

Rubidium chloride is prepared by adding hydrochloric acid to a solution of rubidium carbonate or hydroxide. The solution is evaporated to obtain well-defined colorless cubic crystals of rubidium chloride... 

Elemental analysis Rb 70.68%, Cl 29.32%. Aqueous solution of rubidium chloride may be analyzed for rubidium by AA or ICP and for the chloride anion by ion chromatography or titration with a standard solution of silver... 

Pt(II) compound reactivation, 37 201 Pt(IV) compound reduction, 37 201 rate-determining step, 37 199-201 tetrachloride, 4 187-188 tetracyanide anions, as one-dimensional electrical conductors, 26 235-268 anion-deficient structures anhydrous compounds, 26 252-254 dimerization, 26 249-251 hydrated derivatives, 26 245-252 physics, 26 260-263 with potassium bromide, 26 248-249 with rubidium chloride, 26 249-250 cation-deficient compounds, 26 244, 254-256... 

The preparation of this substance from silver 0-alumina is similar to the preparation of lithium 0-alumina. The melt consists of 10 g of rubidium chloride. The exchange temperature is 800°. For crystals 2 mm in diameter it takes about 16 hours to reach 99% of equilibrium. The rubidium salts used should contain less than 0.02% potassium and less than 0.1% sodium. After decantation of the melt the crystals are washed with water containing 2% propylamine or ethylenediamine to remove residual potassium salts and silver chloride. They are dried at 200°. The rubidium 0-alumina crystals contain less than 0.05 wt % silver. 

Rubidium metal is commercially available in essentially two grades, 99 + % and 99.9 + %. The main impurities are other alkali metals. Rubidium compounds are available in a variety of grades from 99% to 99.99 + %. Manufacturers and suppliers of rubidium metal and rubidium compounds usually supply a complete certificate of analysis upon request. Analyses of metal impurities in rubidium compounds are determined by atomic absorption or inductive coupled plasma spectroscopy (icp). Other metallic impurities, such as sodium and potassium, are determined by atomic absorption or emission spectrograph. For analysis, rubidium metal is converted to a compound such as rubidium chloride. 

Pauling demonstrated that the values of n could be approximated with reasonable accuracy for compounds of ions with noble gas configurations, by averaging empirical constants for each ion. The values of these constants are given in Table 1.15. For example, n for rubidium chloride, RbCl, is 9.5 (average of 9 and 10) and for strontium chloride, SrClz, is 9.33 (the average of 9, 9, and 10). 

Dihydroxo-diaquo-diammino-chromic Chloride, [Cr(NH3), (H20)2(OH)2]Cl, is formed by the addition of ammonia or pyridine to an aqueous solution of tetraquo-diammino-chloride, or saturating an aqueous acetic acid solution with rubidium chloride. It forms light red violet crystals which are insoluble in water. The iodide is obtained from the bromide on addition of potassium iodide to a dilute acetic acid solution of the salt as a light red violet precipitate. The thiocyanate, [Cr(NH3)2(H20)2(OH)2]SCN, is amorphous, and is prepared from the bromide by dissolving in aqueous acetic acid and adding potassium thiocyanate. 

SRM 979), Ni (nickel metal isotopic standard NIST SRM 986), Rb (rubidium chloride isotopic standard NIST SRM 984) and Sr (strontium carbonate isotopic standard NIST SRM 987). In addition, isotope reference materials are available for heavy elements such as T1 (thallium metal isotopic standard NIST SRM 997), Pb (NIST lead standard reference materials SRM 981-983) or U (uranium oxide NIST isotope standard U 005, U020, U350, U500 or U930) and others. The most important isotope standard reference materials applied in inorganic mass spectrometry are summarized in the table in Appendix V.17... 

E. Muller made potassium iodate by electrolyzing the iodide. H. L. Wheeler 44 made rubidium iodate, RbI03, by the action of a mol. of iodine pentoxide on one of rubidium carbonate by treating a hot dil. soln. of iodine trichloride with rubidium hydroxide or carbonate by the action of iodic acid on a hot cone. soln. of rubidium chloride, RbCl. T. V. Barker obtained a good yield by passing chlorine into a hot cone. soln. of a mixture of rubidium iodide and hydroxide whereby the sparingly soluble iodate is precipitated. Caesium iodate, CsI03, was made in a similar way. 

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