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Sodium carbonate dissolving

Ignite the filter in a platinum crucible, fuse with 2.0 g of anhydrous sodium carbonate, dissolve the melt in 40 mL of dilute sulphuric acid, and add 1 mL of sulphurous acid solution (about 6 per cent) to reduce any iron(III) salt, etc., formed in the fusion, and filter if necessary. Transfer the solution to a 100 mL graduated flask, dilute to the mark, and mix. This flask (B) contains the acid-insoluble boron. [Pg.686]

Warning-. CO2 evolution. The sodium chloride-sodium carbonate solution was prepared from 185 g of sodium chloride and 110 g sodium carbonate dissolved in water to give a total volume of 1 L. [Pg.86]

Preparation of Sodium Hydroxide from Sodium Carbonate. Dissolve 14 g of anhydrous sodium carbonate in 100 ml of water. Pour the solution into a 250-300-ml round-bottomed flask. Put pieces of broken chamotte crucible on the bottom of the flask (for what purpose ). Fasten the flask in a stand so that a small space remains between the gauze and the bottom of the flask. Heat the solution in the flask up to boiling and add 8-10 g of triturated calcium hydroxide (in small portions). Insert a funnel into the neck of the flask (for what purpose ) and boil the solution during one hour, adding water from time to time to keep the volume constant. After cooling, filter the solution and measure its volume and density. Use the density value to determine the percentage of sodium hydroxide in the solution. Hand in the alkali solution to the laboratory assistant. [Pg.182]

A translucency liquid in current use is a mixture in equal amounts, of ix-bromonaphthalene and paraffin (G14), but many other solutions have been proposed, including methyl salicylate (L3), 2% sodium carbonate dissolved in equal parts of water and methanol (P6), and Soalex NB (K13). Anisole (P19) is also recommended because reading can be done within 20 minutes, air bubbles seem easy to eliminate, and anisole itself evaporates spontaneously afterward. Sonnet used ethanol for glycoproteins (S22). Some types of varnish have proved useful (D7), but as they dry rather slowly we ourselves have abandoned their use. [Pg.65]

The i-methyl-2-pyridone is salted out of the reaction mixture by the addition of 400-500 g. of anhydrous sodium carbonate to the well-stirred solution. When no more of the sodium carbonate dissolves, the stirring is discontinued and the yellow or brown oily layer containing most of the desired pyridone, together with some of the unreacted pyridinium salt, water, and inorganic salts, is separated from the aqueous mixture. The aqueous mixture is filtered (Note 2) to remove the excess sodium carbonate and the precipitated potassium or sodium ferrocyanide. The filtrate is divided into three portions, each of which is extracted twice with 200-cc. portions of technical iso-amyl alcohol (Note 3). The alcohol used for the second extraction of the first aqueous portion is satisfactory for the first extraction of a second aqueous portion, et cetera, so that a total volume of 800 cc. is used. The iso-amyl alcohol extracts are combined and added to the oily layer which was first separated from the reaction mixture. An aqueous layer usually appears and is separated and extracted with another 100-cc. portion of amyl alcohol. [Pg.42]

Procedure Dissolve 25 grams of rock salt in 75 cc. of water, hastening the action with gentle heating. To the solution add about 1 gram of sodium carbonate dissolved in a few cubic centimeters of water. Stir, let settle, and add a few drops more of sodium carbonate solution, and if no fresh precipitate is produced in the clear part of the solution no more need be added otherwise enough more must be added to produce this result. Filter the solution, hot, through an ordinary filter (Note 4 (c),... [Pg.191]

The nitroxylene is then mixed with 50 kg of sodium carbonate and steam is passed through the mixture to remove unnitrated volatile compounds. The sodium carbonate dissolves in water and the aqueous solution thus formed is separated from nitroxylene. [Pg.412]

Beryllium in lunar, meteorite and terrestrial samples was determined successfully by Eisentraut et al. [632]. The sample was pulverized and fused with sodium carbonate, dissolved in dilute hydrochloric acid and transferred into a polyethylene bottle. After adjusting the pH to about 4, it was further adjusted to 5.0 with acetate buffer, both EDTA and trifluoroacetylacetone in benzene were added and the mixture was heated briefly at 95°C. A PTFE column packed with 10% of SE-30 on Gas-Chrom Z was used and a sensitivity of 4 10"14 g of beryllium was reported for the measurement of peak heights with the use of a tritium-foil ECD. [Pg.196]

A mixture consisting of the Step 4 product (0.773 mmol), thiophene-3-boronic acid (0.938 mmol), tetrakis(triphenylphosphine)palladium(0) (0.004 mmol), 276 mg sodium carbonate dissolved in 1.3 ml water, and 5 ml 1,4-dioxane was refluxed overnight under a nitrogen atmosphere. The reaction was quenched with water, extracted three times with 25 ml CH2C12, dried with Na2S04, filtered, and concentrated. The brown oily residue was purified by chromatography with silica gel using hexane/EtOAc, 1 1, and the product isolated in 48.4% yield. [Pg.623]

It is from the morphine that diamorphine is prepared. This is achieved by mixing the morphine with acetic anhydride and heating to approximately 85°C for about 5 h, or until all of the morphine has dissolved. Water is added to the mixture, followed by activated charcoal which absorbs any impurities. The mixture is repeatedly extracted with charcoal and filtered until the solution is clear. Sodium carbonate, dissolved in hot water, is slowly added to the mixture and the heroin base precipitates as a solid, which is then filtered and dried. The decolourizing and filtering process can be repeated a number of times until the desired colour/purity is achieved. From each kilogram of morphine, up to 700 g of diamorphine can be produced. [Pg.77]

A bottle containing a soln. of 286 4 grms. of decahydrated sodium carbonate dissolved in twice its weight of water is closed by a stopper fitted with a tube-funnel drawn to a very... [Pg.773]

A pH value for 10 gram sodium carbonate dissolved in 100 gram water was 12.7 at 2 C, which is quite strongly alkaline. ... [Pg.108]

Recovery of uranium from leach liquors. Uranium may be recovered from leach liquors by precipitation, ion exchange, or solvent extraction. Precipitation with sodium hydroxide was the recovery method used in the first uranium mills. When used on sodium carbonate leach liquors, the uranium precipitate is fairly free of other metallic contaminants, because sodium carbonate dissolves few other metals beside uranium. However, when used in sulfuric acid leach liquors, the uranium precipitate contains other metals, such as iron dissolved from the ore by the add, and is no longer commercially acceptable. Consequently, in the United States, uranium mills emfdoying add leaching now follow it with selective recovery by either solvent extraction or ion exchange. These processes are described in Secs. 8.5 and 8.6, respectively. [Pg.238]

Fifty grams of the moist basic nitrate is boiled with 200 ml. of 3 iV sodium carbonate solution, the liquor is decanted, and the precipitate is washed with 50 ml. of water. The precipitate is now readily dissolved in concentrated (16 N) nitric acid with the aid of suflficient 3 per cent hydrogen peroxide to reduce cerium (IV) to cerium (III). The solution, when evaporated to a volume of 75 ml. and examined with a hand spectroscope through a thickness of 5 cm., should show no rare earth absorption bands. If bands are evident and a purer cerium preparation is desired, the entire quantity of basic nitrate should be boiled with sodium carbonate, dissolved in nitric acid with the aid of hydrogen peroxide, and the precipitation of the basic nitrate repeated by the described procedure. [Pg.51]

Write a balanced equation for the dissolution of sodium carbonate, NagCOg, in water. Find the number of moles of each ion produced when 0.20 mol of sodium carbonate dissolves. Then, find the total number of moles of ions. [Pg.437]

When sodium carbonate dissolves in water, tbe carbonate ion C03 acts as a base. Write a balanced equation for the reaction of the carbonate ion with water. [Pg.481]

For analysis take 50 ml of the liquid, add 0 4 g of sodium carbonate dissolved in water, boil, filter and wash. To the filtrate add methyl orange and a slight excess of 0 5N hydrochloric acid. Boil for five minutes, neutralise, add an equal volume of glycerol and titrate the boric acid with 0 5N alkali to phenolphthalein or phenol violet. Dry the precipitated zinc carbonate and ignite gently to oxide in a porcelain crucible. ZnO X 3 534 = ZnS04,7H20. [Pg.134]

If a mixed indicator of methyl orange and xylene cyanol is used in the preliminary neutralisation, the end-point can be seen in most cases and direct determination of the boric acid is then possible without ashing. Otherwise, for determination of the borax, ash about 2 g in the presence of an equal weight of anhydrous sodium carbonate, dissolve in hot water and titrate by the method given above for boric acid after neutralising to methyl orange. [Pg.137]

Beaker 1). Prepare 1 gm of Lead Acetate (CH3COO)2Pb with water in a beaker. Add 0.3 gm Na2C03 (Sodium Carbonate). Dissolve it well. [Pg.19]


See other pages where Sodium carbonate dissolving is mentioned: [Pg.179]    [Pg.288]    [Pg.27]    [Pg.236]    [Pg.294]    [Pg.382]    [Pg.639]    [Pg.927]    [Pg.162]    [Pg.50]    [Pg.114]    [Pg.133]    [Pg.170]    [Pg.904]    [Pg.170]    [Pg.179]    [Pg.288]    [Pg.179]    [Pg.288]    [Pg.94]    [Pg.206]    [Pg.552]    [Pg.574]   
See also in sourсe #XX -- [ Pg.107 ]

See also in sourсe #XX -- [ Pg.107 ]




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