Caesium sulphate

The preparation oi the alkali bromides.—While V. Merz and W. Weith 2 found that metallic sodium reacts very slowly with bromine such that even after the two elements have been kept for 8 hrs. at 200°, the conversion of sodium into the bromide is but superficial potassium, caesium, and rubidium unite with bromine more quickly, forming the alkali bromide. The bromides are also formed when hydro-bromic acid is neutralized with the alkali hydroxide or carbonate, and the soln. evaporated. This method, for example, has been used for preparing rubidium bromide, RbBr. C. Chaubrie and N. N. Beketofi made a soln. of caesium bromide, CsBr, by the double decomposition of caesium sulphate, and barium bromide. P. Klein 3 made lithium bromide by digesting calcium bromide with lithium carbonate... 

The alkali sulphates can also be made by neutralizing, say, a soln. of 5 grms. of sulphuric acid in 30 c.c. of water with the alkali hydroxide or carbonate, and evaporating the soln. until crystals begin to form. The process is not economical except on a small scale. It is used mainly for lithium, rubidium, and caesium sulphates. H. Erdmann 20 treated a hot soln. of crude rubidium iron alum with milk of lime made from purified lime, and filtered the liquid from the excess of lime, calcium sulphate, and ferric hydroxide, by suction. The small amount of lime in soln. is precipitated by adding rubidium carbonate. The filtrate is neutralized with sulphuric acid, and evaporated to the point of crystallization. 

The replacement of potassium by rubidium, or rubidium by csesium, produces a regular increase in the dimensions of the crystal, and the same regularities occur in the optical properties. The same regularities do not occur with sodium and lithium. A. Ogg and F. L. Hopwood have calculated the lengths of the sides and the volume of the unit rhomb of the crystals potassium, rubidium, and caesium sulphates from data furnished by the X-ray spectrometer they find... 

The indices of refraction61 of crystals of potassium, rubidium, and caesium sulphates have been measured by A. E. H. Tuttou, H. Topsoe, and C. Christiansen. A. E. H. Tutton s values at 18°-20° are ... 

Aluminium hromide [7727-J5-3] M 266.1, m 97", b 114"/10mm. Refluxed and then distilled from pure aluminium chips in a stream of nitrogen into a flask containing more of the chips. It was then distd under vacuum into ampoules [Tipper and Walker JCS 1352 7959]. Anhydrous conditions are essential, and the white to very light brown solid distillate can be broken into lumps in a dry-box (under nitrogen). Fumes in moist air. Aluminium caesium sulphate (I2H2O) [14284-36-7] M 568.2. Crystd from hot water (3ml/g),... 

Aluminium caesium sulphate (I2H2O) [14284-36-7] M 568.2. Crystd from hot water (3ml/g). 

This alum is of interest inasmuch as its formation renders it easy to separate rhodium from iridium. The sulphates of the metals, dissolved in acidulated water, are treated with caesium sulphate and evaporated. The rhodium alum crystallises out in a pure state, entirely free from iridium.1... 

Caesium bromide, CsBr.—The bromide is produced by the interaction of caesium sulphate and barium bromide.7 It forms anhydrous8 cubic crystals, melting at 627° C., and boiling at 1800° C.9 The vapour-pressure in atmospheres is given by the expression10... 

Caesium iodide, Csl.—The iodide is prepared by the action of caesium sulphate on barium iodide. It forms crystals, melting at 621 0° C.,15 and boiling at 1280° C.,16 the vapour-pressure in atmospheres corresponding with the expression17... 

Cflftsinm nitrite, CsN02.—The nitrite is prepared by the interaction of caesium sulphate and barium nitrite, and forms a yellowish, hygroscopic, crystalline massrf1 A number of double and triple salts of the nitrite with other metallic nitrites have been prepared.12... 

The relatively low solubility of the caesium salt is remarkable in view of the great solubility of ferrous caesium sulphate (see p. 156). 

The reactions of rubidium and caesium sulphates with barium halides in the solid state and under anhydrous conditions have been studied. With BaCl2, BaBr2, or Bal2, reaction proceeds in two stages in the absence of air to produce BaS04 and the alkali-metal halide at 828—963 K. Conductivity and thermal measurements showed that the exothermic first stage involved formation of a ternary eutectic, whereas the second stage was endothermic. A combination of... 

Caesium sulphate Cesium sulfate Dicesium sulfate EINECS 233-662-6 Sulfuric acid, dicesium sail. Used In brewing, mineral waters, for density gradient in ultracentrifuge separation. Crystals mp = 1019° d = 4,24 soluble in H2O, insoluble in organic solvents. Atomergic Chemetals Cabot Carbon Ltd. Cerac Sigma-Atdrich Fine Chem. 

The temperature dependence of the quadrupole splitting of the iron(II) potassium, rubidium, and caesium sulphates has also been examined but in less detail. As can be seen from Table 6.3 they appear to resemble the ammonium salt closely [44]. 

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