Barium chloride, effect

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. 

Barium sulphate exhibits a marked tendency to carry down other salts (see co-precipitation, Section 11.5). Whether the results will be low or high will depend upon the nature of the co-precipitated salt. Thus barium chloride and barium nitrate are readily co-precipitated. These salts will be an addition to the true weight of the barium sulphate, hence the results will be high, since the chloride is unchanged upon ignition and the nitrate will yield barium oxide. The error due to the chloride will be considerably reduced by the very slow addition of hot dilute barium chloride solution to the hot sulphate solution, which is constantly stirred that due to the nitrate cannot be avoided, and hence nitrate ion must always be removed by evaporation with a large excess of hydrochloric acid before precipitation. Chlorate has a similar effect to nitrate, and is similarly removed. 

Discussion. The turbidity of a dilute barium sulphate suspension is difficult to reproduce it is therefore essential to adhere rigidly to the experimental procedure detailed below. The velocity of the precipitation, as well as the concentration of the reactants, must be controlled by adding (after all the other components are present) pure solid barium chloride of definite grain size. The rate of solution of the barium chloride controls the velocity of the reaction. Sodium chloride and hydrochloric acid are added before the precipitation in order to inhibit the growth of microcrystals of barium sulphate the optimum pH is maintained and minimises the effect of variable amounts of other electrolytes present in the sample upon the size of the suspended barium sulphate particles. A glycerol-ethanol solution helps to stabilise the turbidity. The reaction vessel is shaken gently in order to obtain a uniform particle size each vessel should be shaken at the same rate and the same number of times. The unknown must be treated exactly like the standard solution. The interval between the time of precipitation and measurement must be kept constant. 

The separation of impurities such as calcium, barium and radium can be effected by the precipitation of their sulfates. In the case of sulfuric acid leaching of uraninite ore, the leach liquor contains radium which is removed if barium chloride is added since barium sulfate acts as a carrier for radium sulfate. 

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],... 

The removal of inorganic salts from reaction mixtures afforded by polymeric materials may be simply and effectively accomplished by dialysis,166 178 after decomposition of remaining periodate with ethylene glycol130 131 or butylene glycol. 161 170 Alternatively, the iodate and periodate ions may be removed as such, or after reduction to free iodine. The iodate and periodate ions have been effectively precipitated by means of sodium carbonate plus manganous sulfate,6 or by lead dithionate,191 barium chloride,24 192 193 strontium hydroxide194 202 or barium hydroxide,203 204 lead... 

Theory The limit test for sulphates is based upon its precipitation as barium sulphate in the presence of barium chloride, hydrochloric acid and traces of barium sulphate. In this combination, hydrochloric acid exerts its common ion effect whereas traces of BaS04 aids in the rapid and complete precipitation by seeding. Thus, the opalescence caused by the sample is compared immediately with a standard turbidity produced with a known amount of the S042 ion. 

The effect of humidity on combustibility of various mixtures of organic matter and sodium chlorate was studied. Addition of a proportion of hygroscopic material (calcium or magnesium chlorides) effectively reduces the hazard. Similar effects were found for sodium dichromate and barium chlorate. 

Olpe H, Kolb CN, Hausdorf A, et al 4-Aminopyridine and barium chloride attenuate the anti-epileptic effect of carbamazepine in hippocampal slices. Experientia 47 254-257, 1991... 

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). 

Pour 2 ml of the prepared colloidal iron hydroxide solution into each of several test tubes and add 2 ml of one of the following solutions of the same normality (0.1 N) to each of them sodium chloride, barium chloride, aluminium chloride, sodium sulphate, aluminium sulphate, or monosubstituted sodium orthophosphate. What do you observe How does the coagulating effect of an electrolyte depend on the sign and magnitude of the charge of its ions ... 

Radioactive metal wastes from the nuclear industry are of increasing concern as the amount of waste to be disposed of increases. Current treatment of nuclear wastewater involves the addition of lime, which is effective in precipitating most metals out of solution with the exception of radium (Tsezos Keller, 1983). Barium chloride (BaCl2) is used to precipitate radium from sulfur-rich effluents as barium-radium sulfate. Other treatment methods include incineration for some solid wastes, and filtration, adsorption and crystallization for liquid wastes (Godbee Kibbey, 1981). 

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... 

Other physical phenomena that may be associated, at least partially, with complex formation are the effect of a salt on the viscosity of aqueous solutions of a sugar and the effect of carbohydrates on the electrical conductivity of aqueous solutions of electrolytes. Measurements have been made of the increase in viscosity of aqueous sucrose solutions caused by the presence of potassium acetate, potassium chloride, potassium oxalate, and the potassium and calcium salt of 5-oxo-2-pyrrolidinecarboxylic acid.81 Potassium acetate has a greater effect than potassium chloride, and calcium ion is more effective than potassium ion. Conductivities of 0.01-0.05 N aqueous solutions of potassium chloride, sodium chloride, potassium sulfate, sodium sulfate, sodium carbonate, potassium bicarbonate, potassium hydroxide, and sodium hydroxide, ammonium hydroxide, and calcium sulfate, in both the presence and absence of sucrose, have been determined by Selix.88 At a sucrose concentration of 15° Brix (15.9 g. of sucrose/100 ml. of solution), an increase of 1° Brix in sucrose causes a 4% decrease in conductivity. Landt and Bodea88 studied dilute aqueous solutions of potassium chloride, sodium chloride, barium chloride, and tetra-... 

The health effects of the different barium compounds depend on how well the specific barium compound dissolves in water. For example, barium sulfate does not dissolve well in water and has few adverse health effects. Doctors sometimes give barium sulfate orally or by placing it directly in the rectum of patients for purposes of making x-rays of the stomach or intestines. The use of this particular barium compound in this type of medical test is not harmful to people. Barium compounds such as barium acetate, barium carbonate, barium chloride, barium hydroxide, barium nitrate, and barium sulfide that dissolve in water can cause adverse health effects. Most of what we know comes from studies in which a small number of individuals were exposed to fairly large amounts of barium for short periods. Eating or drinking very large amounts of barium compounds that dissolve in water may cause paralysis or death in a few... 

Studies regarding respiratory effects in animals following inhalation exposure to barium are limited to two reports (Hicks et al. 1986 Tarasenko et al. 1977). Pulmonary lesions (perivascular and peribronchial sclerosis and focal thickening of the interalveolar septa) were observed in rats following intermediate inhalation exposure to 3.6 mg barium/m as barium carbonate dust (Tarasenko et al. 1977). Bronchoconstriction was reportedly noted in guinea pigs following inhalation for an unspecified period of time to 0.06 mg barium/m /min as aerosolized barium chloride solution (Hicks et al. 1986). 

Cardiovascular effects have been evaluated in acute, intermediate, and chronic oral studies with experimental animals. Acute studies have been limited to histological examination of the heart following 1-day or 10-day gavage exposure of rats to doses as high as 198 mg barium/kg/day as barium chloride (Borzelleca et al. 1988). No microscopic lesions of the heart were observed. Other cardiovascular parameters were not evaluated. 

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