Barium Acetate Solution

The determination of CEC is commonly made by leaching a soil with a neutral barium acetate solution. It may also be made by extracting a soil with normal ammonium acetate solution, followed by normal potassium chloride. The ammonium removed by the potassium chloride is a measure of the CEC of the.-soil, which includes the cations held by both the organic and inorganic portions. Separate determinations of these portions can be made but less accurately because the separation of one from the other cannot be made without affecting the chemical nature of the organic colloid. 

Figure 2 Thin-layer electrophoresis of uronic acids on silanized silica gel, pretreated with octanol-1 in 0.07 mol I barium acetate solution. Electrophoresis 400V, ISOmin, 16°C. Lanes (1) galactu-ronic acid, (2) mannuronic acid, (3) glucuronic acid, (4) hydrolysate of gum arable (glucuronic acid), (5) hydrolysate of sodium alginate (mannuronic and guluronic acids), (M) mixture of (1-3) and guluronic acid, (H) omega-hydroxymethylfurfural. Sample loading 10 pg of each individual compound. Visualization with naphthoresorcinol-sulfuric acid. Origin indicated.

Monophosphate II. The thioether riboside, 489.5 mg (1 mmole), is dissolved in 8 ml of dry triethyl phosphate, and 1 ml of freshly distilled POCI3 is added at temperatures below 0° in small portions the solution is maintained at 0 for 20 hr. Thereafter, 20 ml of 1 barium acetate solution are added with vigorous stirring while the mixture is cooled to below 20°. After addition of 80 ml of water, the pH is held between 7 and 8.5 by the addition of triethylamine. When all the POCI3 is hydrolyzed, the pH is adjusted to 8.5 and the precipitated barium phosphate is removed by centrifugation. The precipitate is redissolved at pH 2.0 and reprecipitated at pH 8.5 several times to wash out the coprecipitated barium salt of the desired nucleotide. The combined supernatant fluids are mixed with 3 volumes of ethanol. After standing at 0° for 3 hr, the precipitated barium salt of the monophosphate is isolated by centrifugation and washed 3 times with 80% ethanol and with ether. 

Lee and Zhang synthesized barium titanate aqueous sol (Lee and Zhang, 2001). They used barium acetate dissolved in acetic acid. An aqueous solution of an equimolar titanium bis(ammonium lactato) dihydroxide, which was perhaps 50 wt%, was added to the barium acetate solution. After adjusting the concentration by diluting with water/ethanol, the solution was refluxed at 100 C for 8 h, and a viscous barium titanate sol with pH of 10.6 resulted. This solution was used for preparation of thin films by spin-on process. It is very... 

An automatic titrator is used, connected to a conductivity meter with millivolt output. A 5-mL buret glassware unit is suitable. Weigh a sample of about 4 g into a 100-mL volumetric flask and dissolve and dilute to volume with 1 1 THF/water. Depending on the expected S04 content, transfer an aliquot of 1 to 10 mL into the conductometric titration cell. Add 5 mL acetate buifer solution (pH 4.62) and 5 mL THF as well as 1 or 2 drops of an aqueous suspension of barium sulfate (freshly shaken). If the liquid level of the cell is too low, add 1 1 THF/water as necessary to properly immerse the electrodes. Thermostat the cell at 25°C (or other convenient temperature) and titrate with 0.1 M barium acetate solution (dissolved in 1 1 THF/water, in which 20% of the water is the pH 4.62 acetate buffer solution) with stirring. 

In metallic form, barium is very reactive, reacting readily with water to release hydrogen. In aqueous solution it is present as an ion with a +2 charge. Barium acetate, chloride, hydroxide, and nitrate are water-soluble, whereas barium arsenate, chromate, duoride, oxalate, and sulfate are not. Most water-insoluble barium salts dissolve in dilute acids barium sulfate, however, requkes strong sulfuric acid. 

Barium acetate [543-80-6] Ba(C2H202)2, crystallines from an aqueous solution of acetic acid and barium carbonate or barium hydroxide. The level of hydration depends on crystallization temperature. At <24.7°C the trihydrate, density 2.02 g/mL is formed from 24.7 to 41 °C barium acetate monohydrate [5908-64-5] density 2.19 g/mL precipitates and above 41 °C the anhydrous salt, density 2.47 g/mL results. The monohydrate becomes anhydrous at 110°C. At 20°C, 76 g of the monohydrate dissolves in 100 g of water. Barium acetate is used in printing fabrics, lubricating grease, and as a catalyst for organic reactions. 

Barium acetate reagent, 0.5 M, pH 7.0 - dissolve 127.7 g barium acetate [Ba(CH3COO)2l in water and make up to 1 I. Adjust to pH 7.0 using acetic acid and/or barium hydroxide solution as appropriate. 

The solution is concentrated and the anhydrous barium acetate crystallizes at a temperature above 41°C. At temperatures between 25 to 40°C, barium acetate monohydrate, Ba(C2H302)2 H2O [5908-64—5] (density 2.19 g/cm ) crystallizes out of solution. 

Barium acetate also may be prepared by treating barium sulfide with acetic acid, followed by slow evaporation and subsequent crystallization of the salt from the solution ... 

Barium acetate converts to barium carbonate when heated in air at elevated temperatures. Reaction with sulfuric acid gives harium sulfate with hydrochloric acid and nitric acid, the chloride and nitrate salts are obtained after evaporation of the solutions. It undergoes double decomposition reactions with salts of several metals. For example, it forms ferrous acetate when treated with ferrous sulfate solution and mercurous acetate when mixed with mercurous nitrate solution acidified with nitric acid. It reacts with oxahc acid forming barium oxalate. 

For each patient sample, 10 and 20 pi of leukocyte homogenate are transferred to individual wells on the microtiter plate. As two different incubation times are necessary, the same volumes of all samples are also pipetted into the lower part of the plate. Subsequently, 100 pi of substrate buffer is added to each well and the volume is adjusted to a total of 150 pi by adding sodium acetate buffer containing barium acetate. Arylsulfatase A will be inhibited in the presence of barium ions. The plate is briefly shaken, sealed with tape, and covered with aluminum wrapping. Incubation is carried out at 37°C for 30 min (upper half including the standard curve) and 90 min (lower half). The reaction is stopped with 200 pi stop solution and the absorbance is read at 490 nm. 

Sulphuric Acid. — On boiling a mixture of 10 cc. of acetic acid and 150 cc. of wrater, and then adding barium chloride solution, no precipitate of barium sulphate should form on standing twelve hours. 

Tartaric Acid and Sulphates. — On adding potassium acetate and barium nitrate solutions to a solution of 1 gm. of succinic acid in 20 cc. of water, no precipitate should form on standing twelve hours. 

Sulphates. — A mixture of 10 cc. of ammonium thioacetate solution with 10 cc. of diluted acetic acid should not immediately be rendered turbid on the addition of barium chloride solution. 

Chlorides. — The solution of 1 gm. of barium acetate in 20 e.c.. or water, acidulated with nitric acid, must exhibit no turbidity on the addition of silver nitrate solution. 

Calcium and Alkalies. — Dissolve 5 gm. of barium acetate in 200 oc. of water, add to the solution 2 cc. of hydrochloric acid and heat to boiling. Now add 15 cc. of 16 per cent sulphuric acid, allow to stand twelve hours, filter, and mix the. filtrate with 85 per cent alcohol. At most a faint opalescence should be observed and on evaporating in a platinum dish and igniting, not more than 0.004 gm. of residue should remain. 

Nitrates. — The blue color imparted by 1 drop of 1 1000 indigo solution to a solution of 1 gm. of barium acetate in 10 cc. of water should not disappear on the addition of 10 cc. of concentrated sulphuric acid. 

Sulphides.—The 1 20 aqueous solution of barium hydroxide, when acidulated with hydrochloric acid, should not have an odor of hydrogen sulphide, nor should it acquire a dark color on adding lead acetate solution. 

Sulphates, Copper, and Alkalies. — Boil for a few minutes a solution of 5 gm. of ferrous chloride in 10 cc. of water and 5 cc. of nitric acid (sp. gr. 1.3), dilute to 120 cc., add 20 cc. of ammonia water, and filter evaporate 50 cc. of the filtrate and ignite the residue. The weight of the latter should not exceed 0.001 gm. Slightly acidulate 20 cc. of the filtrate with hydrochloric acid and add barium nitrate solution. No change should appear. 20 cc. of the filtrate acidified with acetic acid should show no change upon addition of potassium ferrocyanide solution. 

Sulphates. — Dilute 10 cc. of potassium acetate solution with 10 cc. of water, acidify with hydrochloric acid and add barium chloride solution. No change should appear. 

Sulphates. Tim solution of I gin. of uranium acetate in 20 n. ul wain- and 2 to, i ee. of dilute, acetic, acid should not be nlTcrtcd by barium chloride solution. 

A mixture of 50 g. (0.3 mole) of dZ-glyceric aldehyde acetal (p. 52) and 500 cc. of 0.1 N sulfuric acid is allowed to stand for one week at about 20 0 (Note 1). The mixture is then treated with 30 cc. of glacial acetic acid and neutralized carefully with barium hydroxide solution (Note 2). The mixture is stirred with 5 g. of decolorizing carbon and filtered. The filtrate is evaporated at 10 mm. pressure (Note 3). When no more water can be removed, the residue is treated with an equal volume of absolute alcohol to hasten crystallization. The crystals are collected on a filter and dried in a vacuum desiccator over soda-lime and calcium chloride. The yield of product melting at 137-1390 is 22 g. (80 per cent of the theoretical amount) (Note 4). 

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