Barium chloride, solubility

An esterification agent, sulfurous acid forms dimethyl sulfile (CHjO) SO, bp 126°C and diethyl sulfite (C2H50)2S0, bp 161°C. Sulfites give a white predpitate with barium chloride, soluble in HC1 with evolution of SO . Sulfites decolorize iodine in acid solution. 

Hydrolysis of Potassium Ethyl Sulphate. Dissolve about i g. of the crystals in about 4 ml. of cold distilled water, and divide the solution into two portions, a) To one portion, add barium chloride solution. If pure potassium ethyl sulphate were used, no precipitate should now form, as barium ethyl sulphate is soluble in water. Actually however, almost all samples of potassium ethyl sulphate contain traces of potassium hydrogen sulphate formed by slight hydrolysis of the ethyl compound during the evaporation of its solution, and barium chloride almost invariably gives a faint precipitate of barium sulphate. b) To the second portion, add 2-3 drops of concentrated hydrochloric acid, and boil the mixture gently for about one minute. Cool, add distilled water if necessary until the solution has its former volume, and then add barium chloride as before. A markedly heavier precipitate of barium sulphate separates. The hydrolysis of the potassium ethyl sulphate is hastened considerably by the presence of the free acid Caustic alkalis have a similar, but not quite so rapid an effect. 

These rosin-based sizes, whether paste, Hquid, or emulsions, can be used to size all grades of paper that are produced at acid pH. The latter include bleached or unbleached kraft Hnerboard and bag paper, bleached printing and writing grades, and cylinder board. In addition, polyaluminum compounds have been used in place of alum, most notably, polyaluminum chloride (48), which can reduce barium deposits where these have been a problem. The barium chloride by-product is more water-soluble than barium sulfate. Other polyaluminum compounds such as polyhydroxylated forms of alum and polyaluminum siHcosulfate have been evaluated as alum replacements. 

The more soluble forms of barium such as the carbonate, chloride, acetate, sulfide, oxide, and nitrate, tend to be more acutely toxic (50). Mean lethal doses for ingested barium chloride were 300—500 mg/kg in rats and 7—29 mg/kg in mice (47). 

The threshold of a toxic dose in adult humans is about 0.2—0.5 g Ba the lethal dose in untreated cases is 3—4 g Ba, LD q about 66 mg/kg (47). The fatal dose of barium chloride for humans is reported to be between 0.8 and 0.9 g (0.55—0.60 g of Ba) (50). However, for most of the acid-soluble salts of barium, doses greater than 1 g have been tolerated (51). Lethal doses are summarized in Table 5. Dusts of barium oxide are considered potential dermal and nasal irritants (52). 

The process of isolation finally adopted by the former authors consists in precipitating as reineckates the water-soluble bases contained in a methyl alcoholic extract of the curare. The mixed reineckates are further purified, by solution in acetone and precipitation with water as often as may be necessary. The product so cleaned represents the bulk of the biological activity of the crude drug the mother liquors may contain curine (p. 374), which indicates a menisperm as one of the components of such curares. The mixed reineckates are then fractionated chromato-graphically over alumina and the components isolated as chlorides by the use of silver sulphate and barium chloride in succession. This process has been modified in detail by Schmid and Karrer, who have also found that with their curare, the more soluble reineckate fraction includes less potent quaternary alkaloids. 

Reactions, i. Dissolve a little of the recrystallised salt in water, and add barium chloride solution. There is no precipitate, as the barium salt of ethyl hycliogen sulphate is soluble in water. 

Two grams of the oU are saponified the portion insoluble in water separated by shaking with ether, and the aqueous solution neutralised with acetic acid. The solution is dUuted to 50 c.c. and 10 c.c. of cold saturated solution of barium chloride added. It is then warmed for two hours on a water-bath and allowed to cool. If a crystalline deposit is formed, the oil is to be considered adulterated, as the acids contained in normal lavender oil, acetic and butyric acids, give soluble barium salts. It is evident that this test will only detect those acids whose barium salts are insoluble. A more comprehensive test is therefore needed, as several other esters have since been employed for adulteration purposes. Glycerin acetate, prepared by the acetylation of glycerine, was first de-... 

The aqueous solution will contain the readily water soluble acids such as citric, oxalic and tartaric, etc. This solution should therefore be made just alkaline to phenolphthalein, excess of barium chloride solution added, and the whole warm for about ten minutes. 

Catalytic elfects on the thermal decomposition and burning under nitrogen of the nitrate were determined for ammonium dichromate, potassium dichromate, potassium chromate, barium chloride, sodium chloride and potassium nitrate. Chromium(VI) salts are most effective in decomposition, and the halides salts during burning of the nitrate [1]. The effect of chromium compounds soluble in the molten nitrate, all of which promote decomposition of the latter, was studied (especially using ammonium dichromate) in kinetic experiments [2],... 

Crystallisation was one of the earliest methods used for separation of radioactive microcomponents from a mass of inert material. Uranium X, a thorium isotope, is readily concentrated in good yield in the mother liquors of crystallisation of uranyl nitrate (11), (33), (108). A similar method has been used to separate sulphur-35 [produced by the (n, p) reaction on chlorine-35] from pile irradiated sodium ot potassium chloride (54), (133). Advantage is taken of the low solubility of the target materials in concentrated ice-cold hydrochloric acid, when the sulphur-35 as sulphate remains in the mother-liquors. Subsequent purification of the sulphur-35 from small amounts of phosphorus-32 produced by the (n, a) reaction on the chlorine is, of course, required. Other examples are the precipitation of barium chloride containing barium-1 from concentrated hydrochloric acid solution, leaving the daughter product, carrier-free caesium-131, in solution (21) and a similar separation of calcium-45 from added barium carrier has been used (60). 

Compounds Soluble—barium nitrate, barium sulfide, barium chloride, barium hydroxide, barium acetate insoluble—barium sulfate... 

Reactions in aqueous phase are similar to those of barium chloride. When treated with sulfuric acid, hydrofluoric acid, phosphoric acid or oxalic acid, the insoluble barium salts of these anions are formed. Similarly, many insoluble barium salts may form by double decomposition reactions when treated with soluble salts of other metals. 

Impurities such as heavy metal sulfides are filtered out. Water-soluble sulfur compounds are oxidized to insoluble barium sulfate and removed. The solution is then evaporated to crystaUize barium chloride. 

Elemental composition Ag 69.19%, S 10.28%, O 20.52%. The salt is dissolved in nitric acid, the solution diluted, and analyzed for sdver. It is very slightly soluble in water. The supernatant solution containing trace sulfate anion may be measured by ion chromatography or by treating with barium chloride followed by colorimetric measurement at 420 nm. 

Dr. Crawford showed in this paper that the salt (strontium chloride) obtained by dissolving the new mineral in hydrochloric acid differs in several respects from barium chloride. It is much more soluble in hot water than in cold, the strontium salt is much the more soluble in water and produces a greater cooling effect, and these two chlorides have different crystalline forms. He concluded therefore that the mineral which is sold at Strontean [sic] for aerated terra ponderosa possesses different qualities from that earth, although at the same time it must be admitted that in many particulars they have a very near resemblance to each other. He also stated that it is probable that the Scotch mineral is a new species of earth which has not hitherto been sufficiently examined and that Mr. Babington. . . has for some time entertained a suspicion that the Scotch mineral is not the true aerated terra ponderosa. In 1790 Dr. Crawford sent a specimen of the new mineral (strontianite, strontium carbonate) to Richard Kirwan for analysis (50, 66). 

Dinitro-tetrammino-cobaltic Chloride, [Co(NH3)4(N03)2] Cl, is obtained from the sulphate by treating it with barium chloride, or by heating a solution of dichloro-tetrammino-cobaltic ehloride in dilute acetic acid with sodium nitrite.3 It is soluble in water, and separates from solution in reddish-yellow rhombic crystals. The aqueous solution, however, decomposes on standing. If a cold aqueous solution be treated with dilute nitric acid the nitrate separates concentrated hydrochloric acid decomposes the salt with formation of the chloro-nitro-chloride, [Co(NH3 )4 (NO 2)C1] Cl.3... 

Precipitation of Sparingly Soluble Salts. Pom 2-3 ml of barium chloride, strontium chloride, and calcium chloride solutions into three test tubes. Add a sodium sulphate solution to the first tube, a saturated calcium sulphate solution to the second one, and a saturated strontium sulphate solution to the third one. Write the equations of the chemical reactions in the molecular and net ionic forms. 

For solutions containing sulphuric acid or a sulphate the reagent commonly applied is barium chloride, both when the test is to be qualitative and when quantitative. Precipitation is effected by the gradual addition of barium chloride to the boiling solution containing a little hydrochloric acid, but for the production of pure barium sulphate, and therefore in order to ensure accuracy, certain precautions must be observed.4 Nitrates, perchlorates, phosphates, tervalent metals and large quantities of salts of the alkali metals (particularly potassium) and of the alkaline earth metals are to be avoided, as they cause the precipitated barium sulphate to be rendered impure by occlusion of otherwise soluble substances.5 Such impurities may be accounted for partly by... 

Lead salts similarly yield a precipitate of thiosulphate, soluble in excess of alkali thiosulphate, which also blackens on warming, but the decomposition of the lead thiosulphate is less straightforward, a considerable quantity of sulphur being present in the greyish product.7 Barium chloride with a concentrated solution of an alkali thiosulphate forms a crystalline precipitate of sparingly soluble barium thiosulphate, of which one part dissolves in 480 of water at 18° C.8... 

The alkali nitrososulphonates are decomposed by acids with formation of nitrous oxide and the corresponding sulphate. With barium chloride the nitrososulphonates yield a white precipitate which is soluble in hydrochloric acid.4... 

Dihydroxylamidosulphonic Acid, N(OH)2SQ3H.—A basic salt of this acid having the composition N (OH) (OK )SO 3K has been obtained as the first product of the interaction of sulphur dioxide with a concentrated alkaline solution of potassium nitrite.3 The salt is alkaline in solution and with barium chloride yields a white precipitate, soluble in acids. Sulphuric acid liberates nitrous oxide from it. 

With the exception of the calcium, strontium, barium and mercurous salts, the normal selenates are readily soluble in water. Barium chloride and mercurous nitrate are therefore convenient precipitation agents.6 Barium selenate is, however, more soluble than barium sulphate, and also differs from the latter salt in being slowly reduced to selenite by hydrochloric acid 7 for these reasons precipitation with barium chloride is not applicable to the quantitative determination of selenie acid. A concentrated solution of selenie acid which has been saturated with barium selenate deposits crystals of barium selenie acid, H2[Ba(Se04)2].8... 

The selenotrithionates are rather more stable than the acid, but they yield a precipitate of selenium when warmed with hydrochloric acid. As the barium salt is soluble in water, no precipitate is produced on the addition of barium chloride. 

Solubility and Sulphates. — 3 gm. of calcium oxide slaked with 10 cc. of water should completely dissolve in 15 cc. of hydrochloric acid without effervescence. Dilute the solution with 50 cc. of water, heat to boiling, and add barium chloride solution. On standing twelve hours, not more than a scarcely perceptible, unweighable trace of barium sulphate should be present. 

Barium Oxalo-niobate, 5BaO.Nb2Os.10C2O3.20H2O, does not belong to the alkali series described above. It is prepared either by the addition of barium chloride to a solution of potassium oxalo-niobate, or by digestion of a mixture of barium oxalate and hydrated niobium pentoxide in a solution of oxalic acid. The crystals are soluble in oxalic acid solution but insoluble in water and in cold hydrochloric and nitric acids. 

Barium Orthoarsenite, Ba3(As03)2, has been prepared8 by the addition of potassium orthoarsenite to an aqueous solution of barium chloride and drying the precipitate at 100° C. in a current of hydrogen. It is obtained as a white amorphous powder, readily soluble in hot water and in dilute acids. When heated rapidly to about 730° C. it is decomposed into arsenic and the arsenate 9 the mechanism of the reaction is not understood. Slow heating below 300° C. causes loss of arsenious oxide. 

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