Mixed-salt solutions, carbon dioxide

Solubility of Carbon Dioxide in Aqueous Mixed-Salt Solutions... 

In the present investigation, the solubilities of carbon dioxide in aqueous mixed-salt solutions were measured at 25°C and 1 atm partial pressure of carbon dioxide, and the possibility of a method for estimating the solubility was discussed. 

Table I. Experimental Results of Carbon Dioxide Solubility in Aqueous Binary Mixed-Salt Solutions at 25°C and 1 atm...

In this study, Equation 2 was also used to correlate the solubility data of carbon dioxide in aqueous mixed-salt solutions. The values of A and B, obtained by the least squares method for all the systems, are summarized in Tables V, VI, VII, and VIII. 

In this study, the following equations were developed from Equation 2 to estimate the solubility of carbon dioxide in aqueous mixed-salt solutions from the solubility data in an aqueous solution of each salt component... 

The solubilities of carbon dioxide in aqueous solutions of seven binary and three ternary mixed salts chosen from eight kinds of electrolytes were measured at 25°C and 1 atm partial pressure of carbon dioxide by the saturation method. The experimental results were not correlated easily by the modified Setschenow equation, but they were correlated very well by the empirical two-parameter equation. The parameters in the equation for the binary and ternary solutions could be estimated by assuming an additive rule for the parameters of the component salt systems. This method, therefore, is useful for predicting the solubility of carbon dioxide in aqueous mixed-salt solutions. 

Add 40 ml. of ethyl alcohol to 21 -5 g. of 70 per cent, ethylenediamine solution (0 -25 mol) dissolve 36 -5 g. of adipic acid (0 -25 mol) in 50 ml. of a 6 1 mixture of ethyl alcohol and water. Mix the two solutions, stir and cool. Filter off the resulting salt and recrystalliae it from 60 ml. of a 6 1 ethyl alcohol - water mixture, and dry the salt in the air. Heat the salt in an atmosphere of oxygen-free nitrogen or of carbon dioxide in an oil bath until it melts (ca. 160°) the product will sohdify after a short time. Reduce the pressure to 15 mm. of mercury or less and raise the temperature of the oil bath until the product remelts (about 290°) and continue the heating for 4r-5 hours. Upon coohng, a nylon type polymer is obtained. 

Carbonates. Iron(II) carbonate [563-71-3] FeCO, precipitates as a white soHd when air-free solutions of alkah metal carbonates and iron(II) salts are mixed. The limited tendency of [Fe(H20)g] to hydroly2e is illustrated by the lack of carbon dioxide evolution in this reaction. The soHd rapidly... 

In your laboratory work you will deal mostly with liquid solutions. Liquid solutions can be made by mixing two liquids (for example, alcohol and water), by dissolving a gas in a liquid (for example, carbon dioxide and water), or by dissolving a solid in a liquid (for example, sugar and water). The result is a homogeneous system containing more than one substance—a solution. In such a liquid, each component is diluted by the other component. In salt water, the salt... 

The salt is added to a dilute solution of hydrochloric acid prepared by mixing 300 ml. of water and 56 ml. of concentrated acid (sp. gr. 1.18) the acid should be contained in a 1-1. flask under a reflux condenser. The mixture is warmed gently, whereupon carbon dioxide is evolved and an oil separates. The flask is heated on a steam bath for 1.5 hours, and the oil is then extracted... 

A detailed description of salt mining will be postponed until the next chapter, but it is important to note that soda ash is made from both limestone and salt, the two major raw materials. As outlined in Fig. 5.2, the brine (salt solution) is mixed with ammonia in a large ammonia absorber. A lime kiln, using technology similar to that discussed earlier, serves as the source of carbon dioxide, which is mixed with the salt and ammonia in carbonation towers to form ammonium bicarbonate and finally sodium bicarbonate and ammonium chloride. Filtration separates the less soluble sodium bicarbonate from the ammonium chloride in solution. 

Barium hydroxide decomposes to barium oxide when heated to 800°C. Reaction with carbon dioxide gives barium carbonate. Its aqueous solution, being highly alkahne, undergoes neutrahzation reactions with acids. Thus, it forms barium sulfate and barium phosphate with sulfuric and phosphoric acids, respectively. Reaction with hydrogen sulfide produces barium sulfide. Precipitation of many insoluble, or less soluble barium salts, may result from double decomposition reaction when Ba(OH)2 aqueous solution is mixed with many solutions of other metal salts. 

Rh (NHo) 5C1] (OH) 2, is produced by mixing the chloride with moist silver oxide. Silver chloride is precipitated, and a strongly alkaline liquid produced containing the hydroxide. The base absorbs carbon dioxide from the air, removes ammonia from ammonium salts, and precipitates metallic hydroxides from solutions of the metallic salts. It is only known in solution, and on evaporation of the liquid it is slowly transformed in the cold, more rapidly on heating, into a mixture of aquo-pentammino-rhodium chloride and aquo-pentammino-rhodium hydroxide, thus ... 

The addition of sodium bicarbonate increases the potency of the local anesthetics two to four times for direct application or injection into nerve tranks and probably for subdural injection and on application to mucous surfaces. This is due to the easier penetration of the free anesthetic bases, as compared with their salts. For these purposes, the usual solutions of the anesthetic salts may be mixed with an equal volume of 0.5% sodium bicarbonate solution, without loss of efficiency, and with a saving of one half of the anesthetic, and correspondingly smaller danger of accidents. The mixtures, however, do not keep well, and must be made just before use. Alkalinization or buffering has no advantage for hypodermic or intradermic injections, because these do not require much penetration. Procaine base dissolved by the aid of carbon dioxide is also more potent than the hydrochloride when applied to the cornea, but not for intramuscular injection. 

Lead-II-hydroxide forms a white powder, which readily absorbs carbon dioxide from the air. The exact structure of Lead-II-hydroxide indicates more of a lead-II-oxide hydrate nevertheless, lead-II-hydroxide is prepared by mixing solutions of sodium hydroxide and lead-II-acetate by adding drop wise, the sodium hydroxide solution into the lead-II-acetate solution. The precipitated lead salt is then quickly filtered-off. Lead-II-hydroxide is insoluble in water, but soluble in dilute acids, and alkali hydroxide solutions. 

The salt may be obtained by heating diferrous orthophosphate with water to 250° C. 12 by heating in a sealed tube mixed solutions of sodium phosphate and ferrous sulphate 13 in an atmosphere of carbon dioxide or by electrolysis of sodium phosphate solution, using an iron anode.14... 

Potassium magnesium ferrocyanide, K2MgFe(CN)6, is obtained in the anhydrous condition by mixing cold concentrated solutions of potassium ferrocyanide and magnesium chloride.3 After a short time a white micro-crystalline precipitate is formed, which is not affected by heating to 120° C. When moist the salt soon becomes cream-coloured, owing to slight decomposition, possibly under the influence of atmospheric carbon dioxide. 

The solubility data of carbon dioxide in aqueous solutions of binary mixed salts obtained in this study are summarized in Table I those for ternary mixed salts are summarized in Tables II, III, and IV. Figures 1 and 2 show the solubility data for the potassium chloride-calcium chloride and sodium chloride-sodium sulfate-ammonium chloride mixed solutions, respectively, which are representative of all the data. The salting-out effect was shown in all the systems studied. 

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