Chloride salts, solubility

Gardner and Katritzky (200) prepared and characterized about 24 amirfo- and hydroxypyridine oxides, and showed that 2-hydroxypyridine 1-oxide exists as the strongly hydrogen-bonded l-hydroxypyrid-2-one. Weiss and Harvey (201) described the water-soluble monovalent 6-coordinated silicon chloride salt, soluble in water and alcohol. The tetrachloroferrate (III)... 

The extraction of magnesium chloride from seawater is done first, using solar energy to vaporize a dynamic stream of preconcentrated seawater flowing along an inclined preferential salt separator (PSS). Magnesium chloride salts soluble in seawater will separate as the very end product. Distilled water will be produced as a by-product in this phase. It represents a typical feed of water for hydrogen production by electrolysis. 

The azides are salts which resemble the chlorides in solubility behaviour, for example silver azide, AgNj, is insoluble and sodium azide, NaN3, soluble in water. Sodium azide is prepared by passing dinitrogen oxide over molten sodamide ... 

It was known in the sixteenth century that silver salts were photosensitive, but it was not until the beginning of the nineteenth century, when Herschel found that silver chloride was soluble in sodium thiosulphate, that photography became possible. 

Chloride. Chloride is common in freshwater because almost all chloride salts are very soluble in water. Its concentration is generally lO " to 10 M. Chloride can be titrated with mercuric nitrate. Diphenylcarbazone, which forms a purple complex with the excess mercuric ions at pH 2.3—2.8, is used as the indicator. The pH should be controlled to 0.1 pH unit. Bromide and iodide are the principal interferences, whereas chromate, ferric, and sulfite ions interfere at levels greater than 10 mg/L. Chloride can also be deterrnined by a colorimetric method based on the displacement of thiocyanate ion from mercuric thiocyanate by chloride ion. The Hberated SCN reacts with ferric ion to form the colored complex of ferric thiocyanate. The method is suitable for chloride concentrations from 10 to 10 M. 

Nickel sulfamate is more soluble than the sulfate salt, and baths can be operated using higher nickel concentrations and higher currents. Sulfamate baths have been found to have superior microthrowing power, the abiUty to deposit in small cracks or crevices. Using one nickel salt, only a hydrometer and pH paper are needed to control the bath. A small amount of chloride salt was added as a proprietary. Highly purified nickel sulfamate concentrates are commercially available that can be used to make up new plating baths without further purification. 

The Institut Fran ais du Petrole has developed and commercialized a process, named Dimersol X, based on a homogeneous catalyst, which selectively produces dimers from butenes. The low-branching octenes produced are good starting materials for isononanol production. This process is catalyzed by a system based on a nickel(II) salt, soluble in a paraffinic hydrocarbon, activated with an alkylalumini-um chloride derivative directly inside the dimerization reactor. The reaction is sec-... 

Water soluble salts that are carried over from the desalter. An effective desalting operation is more important than ever when processing heavy feedstocks to the cat cracker. Chloride salts are usually water soluble and are removed from raw crude in the desalter. However, some of these salts can be carried over with desalted crude. 

Hydrochloric acid and sulphuric acid are widely employed in the preparation of standard solutions of acids. Both of these are commercially available as concentrated solutions concentrated hydrochloric acid is about 10.5- 12M, and concentrated sulphuric acid is about 18M. By suitable dilution, solutions of any desired approximate concentration may be readily prepared. Hydrochloric acid is generally preferred, since most chlorides are soluble in water. Sulphuric acid forms insoluble salts with calcium and barium hydroxides for titration of hot liquids or for determinations which require boiling for some time with excess of acid, standard sulphuric acid is, however, preferable. Nitric acid is rarely employed, because it almost invariably contains a little nitrous acid, which has a destructive action upon many indicators. 

Suppose we have a solution that contains lead(II), mercury(I), silver, copper(II), and zinc ions. The method is outlined in Fig. 11.20, which includes additional cations, and is illustrated in Fig. 11.21. Most chlorides are soluble so, when hydrochloric acid is added to a mixture of salts, only certain chlorides precipitate (see Table 11.4). Silver and mercury(I) chlorides have such small values of Ksp that, even with low concentrations of Cl ions, the chlorides precipitate. Lead(II) chloride, which is slightly soluble, will precipitate if the chloride ion concentration is... 

The efficient hydrogenation of various benzene compounds in biphasic systems has also been described by similar surfactant-protected irid-ium(O) nanoparticles [47]. The solubility of the nanoparticles was assured by 10 equivalents of water-soluble N,N-dimethyl-N-cetyl-Ar-(2-hydroxyethyl)-ammonium chloride salt. TEM observations show that the particles are monodispersed in size with an average diameter of 1.9 0.7 nm (Fig. 7). 

Polar substituents have been attached to the porphyrin core in order to achieve water-solubility. (685) has been synthesized by reaction of the Ni11 complex of tetrakis(pentafluorophenyl)-porphyrin with dimethylammonium hydrochloride in DMF, followed by methylation with methyl trifluoromethanesulfonate (triflate) in trimethyl phosphate.1778 The triflate and chloride salts are... 

Non-Aqueous Colloidal Metal Solutions. It has been difficult to prepare colloidal gold in non-aqueous media due to limitations in preparative methods (low salt solubilities, solvent reactivity, etc.), and the fact that the low dielectric constant of organic solvents has hindered stabilization of the particles. In aqueous solution the gold particles are stabilized by adsorption of innocent ions, such as chloride, and thus stabilized toward flocculation by the formation of a charged double layer, which is dependent on a solvent of high dielectric constant. Thus, it seemed that such electronic stabilization would be poor in organic media. 

The chloride salt forms bright yellow needles, which are readily soluble in hot water, ethanol, and such organic solvents... 

In its chemistry, cadmium exhibits exclusively the oxidation state 4- 2 in both ionic and covalent compounds. The hydroxide is soluble in acids to give cadmium(II) salts, and slightly soluble in concentrated alkali where hydroxocadmiates are probably formed it is therefore slightly amphoteric. It is also soluble in ammonia to give ammines, for example [Cd(NH3)4]2+. Of the halides, cadmium-(II) chloride is soluble in water, but besides [Cd(H20)J2+ ions, complex species [CdCl]+, [CdCl3] and the undissociated chloride [CdCl2] exist in the solution, and addition of chloride ion increases the concentrations of these chloro-complexes at the expense of Cd2+(aq) ions. 

For a decade or so [CoH(CN)5] was another acclaimed catalyst for the selective hydrogenation of dienes to monoenes [2] and due to the exclusive solubility of this cobalt complex in water the studies were made either in biphasic systems or in homogeneous aqueous solutions using water soluble substrates, such as salts of sorbic add (2,4-hexadienoic acid). In the late nineteen-sixties olefin-metal and alkyl-metal complexes were observed in hydrogenation and hydration reactions of olefins and acetylenes with simple Rii(III)- and Ru(II)-chloride salts in aqueous hydrochloric acid [3,4]. No significance, however, was attributed to the water-solubility of these catalysts, and a new impetus had to come to trigger research specifically into water soluble organometallic catalysts. 

Sb is oxidized by nitric acid, forming a gelatinous precipitate of bydrated antimony pentoxide. It does not react with cold dilute sulfuric acid. However, reaction occurs in bot concentrated acid an oxysulfate of indefinite composition and low acid-solubdity is formed. It reacts with bydrofluoric acid to form soluble antimony trifluoride and pentafluoride. Hydrochloric acid in the absence of air does not readily attack tbe metal however, finely divided antimony reacts with hot concentrated acid forming chloride salt. 

Holmium chloride is obtained from rare-earth minerals. Recovery steps are discussed above (see Holmium). The rare-earth mineral is cracked by acid attack by heating with hydrochloric acid. The water-soluble chloride salt is filtered and separated from insoluble residues. The hydrated chloride salt is heated at 350°C in a current of hydrogen chloride to yield anhydrous H0CI3. Heating in air in the absence of hydrogen chloride yields holmium oxychloride, HoOCl. Hohnium chloride may be purified by distdlation or vacuum sublimation. 

Uranium mineral first is digested with hot nitric acid. AH uranium and radium compounds dissolve in the acid. The solution is filtered to separate insoluble residues. The acid extract is then treated with sulfate ions to separate radium sulfate, which is co-precipitated with the sulfates of barium, strontium, calcium, and lead. The precipitate is boiled in an aqueous solution of sodium chloride or sodium hydroxide to form water-soluble salts. The solution is filtered and the residue containing radium is washed with boiling water. This residue also contains sulfates of other alkahne earth metals. The sohd sulfate mixture of radium and other alkahne earth metals is fused with sodium carbonate to convert these metals into carbonates. Treatment with hydrochloric acid converts radium and other carbonates into chlorides, all of which are water-soluble. Radium is separated from this solution as its chloride salt by fractional crystallization. Much of the barium, chemically similar to radium, is removed at this stage. Final separation is carried out by treating radium chloride with hydrobromic acid and isolating the bromide by fractional crystallization. 

Also, the chloride salt may be obtained by treating the yellow hydrous oxide, Rh203 5H20, with hydrochloric acid. The solution is carefully evaporated to form a dark red and water-soluble salt, rhodium trichloride tetrahy-drate, RhCl3 4H20. Heating the tetrahydrate in a stream of hydrogen chloride gas at 180°C forms the anhydrous salt, RhCR. 

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