Saturated Cesium

Many of the Vargaftik values also appear in Ohse, R. W., Handbook of Thermodynamic and Transport Properties of Alkali Metals, Blackwell Sci. Pubs., Oxford, 1985 (1020 pp.). This source contains superheat data. 

An extensive review of properties of the solid and the saturated liquid was given by Alcock, C. B., M. W. Chase, et al., 7. Phys. Chem. Ref Data, 23, 3 (1994)  

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In quinoline and isoquinoline, the benzene ring is more receptive to fluorma-tion, its double bonds being saturated and the hydrogen atoms replaced in preference to those in the pyridine ring As with pyridine and its homologues, ring contraction takes place during fluorination with cesium tetrafluorocobaltate at... 

Fluorination. Direct fluorination of quinoline was accompanied by extensive fragmentation of the heteroring, but trifluoromethyl hypofluorite in trichlorofluoromethane at -70°C converted 5-fluoro-8-hydroxyquino-line into the 5,7-difluoro-8-hydroxy product (72JMC987). Quinoline, itself, was perfluorinated by fluorine and cobalt(III) fluoride (56JCS783), whereas cesium tetrafluorocobaltate at around 350°C converted it into a mixture of saturated polyfluoro compounds (82JFC413). It is much more satisfactory to introduce fluorine by nucleophilic methods. 

Carbon Disulfide under Sulfur Compounds Carbon Monoxide under Carbon Compounds Carbon Tetrachloride under Saturated Alkyl Halides Carbon Tetrafluoride under Saturated Alkyl Halides Carboxylic Acids Carboxylic Acids and Derivatives Carboxylic Acids with Other Functional Groups Cesium... 

This vapor pressure can be deduced from kinetic theory and the rate of arrival of Cs atoms per square centimeter per second (3,4). This arrival rate. A, can be calculated from the measured value of the saturation positive ion current. Langmuir first showed that if the tungsten is hot enough every cesium atom that strikes the surface evaporates off as a positive ion of cesium. This saturated positive ion current, i.p, can be measured easily with a medium sensitive galvanometer when the collector is negative. It is related to A by the equation... 

Sorption Capacity. The average sorption capacity of the clay determined from isotopic redistribution of Cs 37 between aqueous 0.01 M CsCl solutions and cesium-saturated clay was 0.9I mequiv./ gm. The average sorntion capacity similarly determined by isotopic redistribution of Ba3-33 vas 0.7U mequiv./gm. The maximum relative error in these capacities was estimated at 10%. 

If those sorption capacities were due to ion exchange, it would be expected that preparation of the cesium- and barium-saturated clays would have caused various counter ions such as those of sodium, potassium, magnesium, and calcium to be desorbed from the clay and to appear in. the 1.0 M solutions. The total... 

When preparing the cesium- and barium-saturated clays, the 1.0 M solutions used were decanted (after centrifuging) and analyzed semiquantitatively by emission spectroscopy. From those analyses, it appears that the following species were desorbed sodium, potassium, calcium, magnesium, and strontium. It further appeared that desorption of potassium was almost unique to cesium sorption whereas, desorption of the other species appeared to be common to both cesium and barium sorption. Small amounts of other elements such as nickel and copper were also detected by the analyses. However, to what extent the observed concentrations may represent desorption and to what extent they may represent the dissolution of sparingly soluble substances (particularly hydroxide species) is as yet-uncertain. The apparent concentrations of the desorbed species per gram of clay are given in Table III. 

Sawhney, B. L., "Sorption and Fixation of Microquantities of Cesium by Clay Minerals Effect of Saturating Cations,"... 

Figure 5.5. Adsorption of cesium (Cs) by Ca-saturated clay minerals with time.Ill, illite Mt. montmorillonite Vr, vermiculite. [From Sawhney (1966), with permission.]...

Solution X-ray diffraction measurements for saturated aqueous solutions of the KCl-MgCl2-6H20 and CsCl-MgCl2-6H20 double salts at 25°C reveal that magnesium(II) ions in the solutions are fully hydrated as [Mg(H20)6]2+ with a Mg-0 bond length of 208-209 pm. This is essentially the same bond length as in the double salt crystals, and the K+ and Cs+ ions have both water molecules and chloride ions in their first coordination sphere. The coordination numbers for water molecules and chloride ions around a K+ ion are 4.7 and 2.4, respectively, and those around a Cs+ ion are 4.7 and 2.0, respectively. The K+-OH2 and K+-C1 interatomic distances are found to be 227 and 320 pm, respectively, and the Cs+-OH2 and Cs + -Cl distances are 315 and 339 pm, respectively (58). The interatomic distances determined are essentially the same as those that have been reported in the literature for aqueous solutions of potassium and cesium salts. 

Initially 1.3 g (22 X 10-3 mole) of Cs2 [Pt(CN)4]-H20 is dissolved in 6 mLof water to produce a saturated solution. It may be necessary to warm the solution slightly to dissolve the Cs2 [Pt(CN)4]-H20. The solution is transferred to a 50-mL polyethylene beaker and 4.0 g (2.6 X 10-2 mole) of cesium fluoride is added. The white cesium fluoride appears to become yellow after it is added. It then dissolves leaving a white suspension. Finally, 3 mL of cone. HF (28.9 M) is added to acidify the solution and dissolve the white suspension. 

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