Sodium chloride nitrate solution, carbon

Figure 5.41 Relationship of PaN0< to carbon number of alkyl groups of a poly (N-n-alky 1-4-vinylpyridinium bromide) layer formed on a membrane surface. AEM anion exchange membrane without a layer CH with a layer of poly(N-n-octyl-4-vinylpyridinium) bromide C with a layer of poly(N-n-dodecyl-4-vinylpyr-idinium) bromide Ct6 with a layer of poly(N-n-hexadecyl-4-vinylpyridinium) bromide. A 0.25 N sodium nitrate and 0.25 N sodium chloride mixed solution was electrodialyzed at 10 mA tcm 2 for 60 min at 25.0 °C, with the polysoap layer on the membrane surface facing the desalting side.

Write balanced molecular and ionic equations showing the following reactions silver nitrate and sodium chloride solutions to form silver chloride and sodium nitrate hydrochloric acid and sodium hydroxide to form sodium chloride and water zinc and copper(ii) sulfate solution to form zinc sulfate and copper sodium carbonate and hydrochloric acid to form sodium chloride, water and carbon dioxide. 

In the hot precipitation method, sodium carbonate solution is added slowly to a refluxing solution of mercuric chloride, followed by an additional reflux period of 1 to 2 h. The washed precipitate is then dried. A variation allows the substitution of mercuric nitrate for the chloride if substantial quantities of sodium chloride are used. Sodium hydroxide, ia the presence of sodium carbonate, is the precipitant. 

Cadmium Hydroxide. Cd(OH)2 [21041-95-2] is best prepared by addition of cadmium nitrate solution to a boiling solution of sodium or potassium hydroxide. The crystals adopt the layered stmcture of Cdl2 there is contact between hydroxide ions of adjacent layers. Cd(OH)2 can be dehydrated to the oxide by gende heating to 200°C it absorbs CO2 from the air forming the basic carbonate. It is soluble ia dilute acids and solutions of ammonium ions, ferric chloride, alkah haUdes, cyanides, and thiocyanates forming complex ions. 

The 0 -(p-nltrophenyl)-a-ethyl-glutarimide starting material can be prepared as follows 217 g of 0 -phenyl-a-ethyl-glutarimlde are dissolved in 800 g of concentrated sulfuric acid with subsequent cooling to about -10°C and nitration Is carried out at -10°to -f10°C by slow addition of a mixed acid consisting of 110 g of concentrated suifuric acid and 110 g of 63% nitric acid. The nitration solution is stirred into ice, the separated nitro compound taken up in methylene or ethylene chloride, the solution washed with water and sodium carbonate solution until... 

Either the Mohr titration or the adsorption indicator method may be used for the determination of chlorides in neutral solution by titration with standard 0.1M silver nitrate. If the solution is acid, neutralisation may be effected with chloride-free calcium carbonate, sodium tetraborate, or sodium hydrogencarbonate. Mineral acid may also be removed by neutralising most ofthe acid with ammonia solution and then adding an excess of ammonium acetate. Titration of the neutral solution, prepared with calcium carbonate, by the adsorption indicator method is rendered easier by the addition of 5 mL of 2 per cent dextrin solution this offsets the coagulating effect of the calcium ion. If the solution is basic, it may be neutralised with chloride-free nitric acid, using phenolphthalein as indicator. 

Saline soils vary considerably in their salt content, type of salt, structure and ease to be reclaimed. Dominant anions are chlorides, sulfates and carbonates, sometimes nitrates and bicarbonates. Sodium salts occur most frequently, but calcium and magnesium compounds are common as well, while mixtures of various salts and complex minerals are not exceptional. The non-salt solution contains mainly calcium salts (50-80%) magnesium (15-35%), potassium (2-5%) and sodium (1-5%) make up the remaining cations. In saline soils, however, the percentage of Ca2+ is lower, and the values of K+, Mg2+ and Na+ is higher. 

In a similar procedure [32] the sediment is wet oxidised with dilute sulphuric acid and nitric acids in an apparatus in which the vapour from the digestion is condensed into a reservoir from which it can be collected or returned to the digestion flask as required. The combined oxidised residue and condensate are diluted until the acid concentration is IN and nitrate is removed by addition of hydroxylammonium chloride with boiling. Fat is removed from the cooled solution with carbon tetrachlodithizone in carbon tetrachloride. The extract is shaken with 0.1M hydrochloric acid and sodium nitrite solution and, after treatment of the separated aqueous layer with hydroxylammonium chloride a solution of urea and then EDTA solution are added to prevent subsequent extraction of copper. The liquid is then extracted with a 0.01% solution of dithizone in carbon tetrachloride and mercury estimated in the extract spectrophotometrically at 485nm. 

Chlorides. — The solution of 5 gm. of sodium carbonate in 50 cc. of water and 10 cc. of nitric acid should not be affected by silver nitrate solution. 

Chlorides and Sulphates. — Decompose 10 gm. of sodium oxalate by heating in a platinum crucible, best over an alcohol lamp (illuminating gas contains sulphur). The carbonate formed is dissolved in nitric acid, and the solution filtered off from the carbon. On adding silver nitrate solution to half of the filtrate, no reaction for hydrochloric acid should be obtained and in the other half no reaction for sulphuric acid should be obtained on adding barium nitrate solution. 

Potassium Niobates are generally produced by fusion of the metal or the pentoxide with potassium hydroxide, potassium carbonate, or potassium nitrate,3 or by the action of solutions of caustic potash or of potassium carbonate on niobic acid.4 They are among the most stable of the niobates their solutions can be boiled without precipitation of the acid. On being treated with sodium salts, for example sodium chloride, sodium niobates are precipitated. 

Fifty grams of pure cobalt carbonate are prepared by slowly adding a saturated solution of the equivalent quantity of the chloride, nitrate, or sulfate to a hot solution of 60g of anhydrous sodium carbonate in 600ml of water. Some effervescence takes place The mixture is digested at the boiling point with continual stirring for at least 16 minutes and then suction-filtered, washed freely with hot water, and pressed as dry as possible mi the filter. Alternatively, 51g of technical cobalt carbonate may be dissolved in the minimum amount of 63f hydrochloric add (about 140ml), filtered, and reprecipitated as described ... 

Salts therefore, are prepared (1) from solutions of acids and bases by neutralization and separation by evaporation and crystallization (2) from solutions of two salts by precipitation where the solubility of the salt formed is slight (e.g., silver nitrate solution plus sodium chloride solution yields silver chloride precipitate [almost all as sulid], and sodium nitrate present in solution as sodium cations and nitrate anions [recoverable as sodium nitrate, solid by separation of silver chlondc and subsequent evaporation of the solution]) (3) from fusion of a basic oxide (or its suitable compound—sodium carbonate above) and an acidic oxide (or its suitable compound—ammonium phosphate), since ammonium and hydroxyl are volatilized as ammonia and water. Thus, sodium ammonium hydrogen phosphate... 

Some salts, such as sodium chloride, copper carbonate and sodium nitrate, crystallise in their anhydrous forms (without water). However, many salts produce hydrates when they crystallise from solution. A hydrate is a salt which incorporates water into its crystal structure. This water is referred to as water of crystallisation. The shape of the crystal hydrate is very much dependent on the presence of water of crystallisation. Some examples of crystal hydrates are given in Table 8.6 and shown in Figure 8.20. 

Sodium Chloride Dissolve about 10 g of sample, accurately weighed, in 50 mL of water in a 250-mL beaker. Add sufficient nitric acid to make the solution slightly acid, then add 1 mL of ferric ammonium sulfate TS and 1.00 mL of 0.05 A ammonium thiocyanate, and titrate with 0.05 A silver nitrate, stirring constantly, until the red color completely disappears. Finally, back titrate with 0.05 A ammonium thiocyanate until a faint red color appears. Subtract the total volume of 0.05 A ammonium thiocyanate added from the volume of 0.05 A silver nitrate required. Each milliliter of 0.05 A silver nitrate is equivalent to 2.922 mg of sodium chloride (NaCl). Calculate the percentage of sodium chloride in the sample taken. Water Calculate the percentage of water by subtracting from 100 the sum of the percentages of Sodium Bicarbonate, Sodium Carbonate, and Sodium Chloride found in the sample. 

Action of heat All chlorates are decomposed by heat into chlorides and oxygen. Some perchlorate is usually formed as an intermediate product. The chloride is identified in the residue by extracting with water and adding dilute nitric acid and silver nitrate solution. An insoluble chlorate should be mixed with sodium carbonate before ignition. 

Alternatively, wash the precipitated halides until free from excess silver nitrate solution, and then treat the precipitate with a cold, freshly prepared solution containing 4 per cent formaldehyde in 0-05m sodium carbonate solution pour a little of the latter reagent through the filter several times. Test the filtrate for chloride with silver nitrate solution and dilute nitric acid. Silver bromide reacts slightly with the reagent yielding a faint opalescence silver iodide is unaffected. 

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