Lithium bromide sulphate

The solubility of sodium chloride in aq. acetone at 20° falls to 27"18 with 10 c.c. of acetone per 100 c.c. of solvent to 0 25 with 90 c.c. of acetone per 100 c.c. of solvent at 0°, 100 grms. of acetone dissolve 4"6 grms. of lithium chloride, and at 58°, 214 grms., so that the solubility is diminished by a rise of temp. The solubility of potassium in aq. soln. of acetone increases from almost zero with 100 per cent, acetone at 20° to 8"46 with 50 per cent, acetone and to 21 "38 with 20 per cent, acetone. At 30°, 100 grms. of a soln. with 696 per cent, acetone carries 23 42 per cent, potassium chloride and the remainder is water 8"06 per cent, of this salt is present in a soln. with 45 98 per cent, acetone and 0-13 per cent, of this salt in a soln. with 89"88 per cent, of acetone. At 40°, a soln. with 15"75 per cent, acetone carries 21 "28 per cent, of potassium chloride and with 79"34 per cent, of acetone there is 0"58 per cent, of potassium chloride. At 40°, therefore, for cone, of acetone between 20 and 80 per cent., the sat. soln. separates into two layers the upper layer has 55 2 per cent, water, 31 "82 acetone, and 12"99 KC1, when the lower layer has 28"14 per cent, water, 69 42 acetone, and 2"44 KC1. Similarly, when the upper layer has water, acetone, and potassium chloride in the respective ratio 46 49, 45"34, and 8 17 the lower layer has 38 68, 56"17, and 5 25. The separation into two layers with sat. soln. of potassium chloride containing 26 per cent, acetone, occurs at 46"5° and the temp, of separation with other proportions of acetone is indicated in Fig. 22. C. E. Linebarger (1892) and J. E. Snell (1898) 34 found the phenomenon also occurs with the chlorides of lithium, ammonium, sodium, rubidium, calcium, strontium, cobalt, and many other radicles also with bromides, sulphates, cyanides, and numerous other salts with aq. acetone,... 

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... 

Chlorotrimethylsilane (2.7 g, 25 mmol) (1) (CAUTION) is added to a solution of lithium bromide (1.74g, 20 mmol) in dry acetonitrile (20 ml) (2) with good stirring under a nitrogen atmosphere. Cinnamyl alcohol (1.34 g, 10 mmol) is then added and the reaction mixture heated under reflux for 12 hours. The progress of the reaction is monitored by t.l.c. on silica gel plates with hexane as the eluant. On completion of the reaction (12 hours), the reaction mixture is taken up in ether (50 ml), washed successively with water (2 x 25 ml), sodium hydrogen carbonate solution (10%, 50 ml) and finally brine, and dried over anhydrous sodium sulphate. Evaporation of the ether affords the pure bromide in 93 per cent yield. The product may be recrystallised from ethanol and has m.p. 31-32 °C CAUTION this compound is lachrymatory. 

The effects of dimethyl sulphoxide, lithium bromide, guanidinium chloride, sodium dodecyl sulphate, and urea on lysozyme have been studied using Raman spectroscopy. The spectrum observed was found to depend on the denaturant used, suggesting there is not a unique denatured state for lysozyme. An analysis of the interaction of sodium dodecyl sulphate with lysozyme has been published. A kinetic study of the denaturation and subsequent reduction of disulphide bonds in lysozyme has been made using rapid ultrasonic absorption measurements. 

The bromide-lithium exchange of l,l-dibromo-2,2-diphenylethylene (88) was thoroughly examined by Maercker and coworkers. It could be shown that the number of side-products drastically decreases when LiDBB instead of metallic lithium is used as lithiation agent. The reaction was performed in THF at low temperatures by addition of the solution of the geminal dibrominated aUcene to the solution of LiDBB (Scheme 32). By this method, l,l-dilithio-2,2-diphenylethylene (89) could be obtained in 36% yield together with the 1,4-dilithium compound 48 and monolithiated 47 (51 and 2%, respectively). The yields were determined after trapping the reaction mixture with dimethyl sulphate. 

The chlorides, bromides, iodides, and cyanides are generally vigorously attacked by fluorine in the cold sulphides, nitrides, and phosphides are attacked in the cold or may be when warmed a little the oxides of the alkalies and alkaline earths are vigorously attacked with incandescence the other oxides usually require to be warmed. The sulphates usually require warming the nitrates generally resist attack even when warmed. The phosphates are more easily attacked than the sulphates. The carbonates of sodium, lithium, calcium, and lead are decomposed at ordinary temp, with incandescence, but potassium carbonate is not decomposed even at a dull red heat. Fluorine does not act on sodium bofate. Most of these reactions have been qualitatively studied by H. Moissan,15 and described in his monograph, Lefluor et ses composes (Paris, 1900). 

According to F. C. Franklin and C. A. Kraus,40 liquid ammonia readily dissolves sodium and potassium iodides. The partial press, of ammonia in soln. of potassium iodide at 25°, as measured by R. Abegg and H. Riesenfeld, is raised from 13 45 mm. of water to 13 28, and 14 88 mm. for 0 5W-, N-, and l 5Ar-soln. respectively. H. M. Dawson and J. McCrae have shown that the distribution of ammonia between water and chloroform is generally lowered by the addition of various salts of the alkali metals and ammonium which they tried—halides, nitrates, chlorates, oxalates, sulphates, carbonates, hydroxides this means that the solvent power of aq. soln. of the alkali salts is in general less than that of pure water—lithium chloride, ammonium bromide, and sodium iodide act in the opposite way. The other halide salts of lithium were not tried. The change produced in the partition coeff. by the halides, at 20°, is as follows ... 

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. 

Jones and Tarter [11] have applied this technique to the simultaneous determination of metals (sodium, potassium, calcium, magnesium) and anions (chloride, sulphate, nitrate, bromide) in potable waters. The technique uses a cation separator column, a conductivity detector, an anion separator column and an anion suppressor column. Two different eluants were used lithium carbonate-lithium acetate dihydrate, and copper phthalate. 

Sodium chloride Sodium bromide Sodium iodide Sodium sulphate Sodium silicate Potassium sulphate Lithium chloride Calcium carbonate Calcium sulphate Magnesium sulphate Manganous carbonate Ferrous carbonate. Aluminium phosphate Ammonium nitrate Organic matter... 

Perman2 exposed solid cupric nitrate and sulphate and auric chloride, contained in quartz vessels at a pressure of 0-1 mm., to the action of radium bromide for four months, but in no instance could the development of lithium be detected by the spectroscope. 

Idthium Bromide—Litkii bromidum U. S.)—LlBr—87—is formed by decomposing lithium sulphate with potassium bromide or by satux ating a solution of HBr with lithium carbonate. It crystallizes in very deliquescent, soluble needles. 

As the bromides complicate the measurement of the half-wave potentials of positive waves, separate the brominated products by extraction into ether. Distil off the ether, dissolve the residue, and polarograph in 0 1 N lithium sulphate and 50 per cent methanol. 

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