Barium solution

Because of its high reactivity, production of barium by such processes as electrolysis of barium compound solution or high temperature carbon reduction is impossible. Electrolysis of an aqueous barium solution yields Ba(OH)2, whereas carbon reduction of an ore such as BaO produces barium carbide [50813-65-5] BaC2, which is analogous to calcium carbide (see Carbides). Attempts to produce barium by electrolysis of molten barium salts, usually BaCl25 met with only limited success (14), perhaps because of the solubiUty of Ba in BaCl2 (1 )-... 

When a substance made up of ions is dissolved in water, the dissolved ions behave independently. That is, they undergo their own characteristic reactions regardless of what other ions may be present. For example, barium ions in solution, Ba2, always react with sulfate ions in solution, S04 , to form an insoluble ionic compound, BaS04(s), no matter what other ions are present in the barium solution. If a solution of barium chloride, BaCK, and a solution of sodium sulfate, Na S04, arc mixed, a white solid, barium sulfate, is produced. The solid can be separated from the solution by filtration, and the resulting solution contains sodium chloride, just as it would if solid NaCl were added to water. In other words, when the two solutions are mixed, the following reaction occurs ... 

Barium Solution ASp Dissolve 1.778 g of BaCl2 in sufficient water to produce 1000 ml. Dilute it with water so that 1 ml contains 1 mg of Ba. 

An approximate determination may be made by means of the barium chloride solution prepared for determining the extent of plastering. To this end, separate quantities of 50 c.c. of the wine are treated with different volumes of the barium solution until a filtrate is obtained which remains almost clear with a drop of either the barium solution or dilute sulphuric acid the amount of the reagent used gives approximately the quantity of sulphates present. 

The absorbance at the band maximum for solutions of lithium, sodium, and barium in ND8 is a linear function of the concentration, and extrapolation of the linear function to zero concentration predicts zero absorbance (Figure 5 and Table II). The molar extinction coefficients as calculated by the least squares method for solutions of lithium, sodium, and barium in ND8 at —70° C. are given in Table II. If it is assumed that barium loses two electrons upon solvation, the molar extinction coefficients of lithium, sodium, and barium solutions are the same to within the estimated error of measurement (4%). The residual absorbance, as calculated from the least squares analysis, in each case is... 

Barium is bivalent in its salts forming the barium(II) cation Ba2+. Its chloride and nitrate are soluble, but on adding concentrated hydrochloric or nitric acids to barium solutions, barium chloride or nitrate may precipitate out, as a consequence of the law of mass action. 

BaSO Cs), no matter what other ions are present in the barium solution. If solutions of barium chloride and sodium sulfate are mixed, a white solid, barium sulfate, is produced. The sohd can be separated from the solution by filtration, and the resulting solution contains sodium chloride, just as it would if sohd NaCl were added to water. 

Hemandez-Guijo JM, de Pascual R, Garcia AG, Gandia L. Separation of calcium channel current components in mouse chromaffin cells superfused with low- and high-barium solutions. Pflugers Arch 1998 436(l) 75-82. 

Figure 9.4 Using barium solutions to test for anions...

Make a standard zinc solution by dissolving 7-70 g of zinc in about 75 ml of dilute hydrochloric acid, adding excess of ammonia solution and diluting to 1 litre. Make an alkaline lead solution by dissolving 1 g of lead acetate in about 20 ml of hot 5 per cent potassium hydroxide solution and diluting to 100 ml. Heat to boiling about 1 g of barium sulphide in about 50 ml of water and titrate with the standard zinc solution until no black or brown colour is obtained by adding a drop of the filtered barium solution to a drop of the lead indicator, spotted on a porcelain tile. 1 ml zinc solution = 0 0201 g BaS. 

Sulphamic acid solution liberates sulphate ions slowly on boiling. When mixed with the barium solution, barium sulphate precipitates slowly giving a more easily filtrable precipitate. NH2S0jH+H20-+NH4++S04 -+H+... 

Aspirate at about 2.5 to 3 mL/min a standard barium solution into the flame. Make adjustments to the height and angle of the burner and to the acetylene flow rate to give maximum absorption. Make sure that standard (d) in 6.6 still gives zero absorbance by making adjustments, if necessary. 

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