Oxides Slightly soluble

Properties A greenish-yellow gas with a characteristic pungent odor. Forms compounds with virtually all elements. Strong oxidizer. Slightly soluble in water. Can be readily liquified under pressure. Very toxic. 

If Q values actually reflect the primaiy medium effect of 0 , they cause that the above-mentioned melts as extremely aggressive acidic media, likely because of performance of anhydrous sulfuric acid in comparison with water (Hq -logy + = -11 In particular, such melts should completely dissolve appreciable quantities of solid oxides, e g., MgO, NiO, etc., up to 1 mol kg. For instance, MgO, which is practically insoluble in KCl-NaCl equimolar mixture (pK = 9.33 0.06 can be characterized by pK 1 (because 9.33 - 8 1) in KCl-LiCl eutectic that corresponds to the value of the solubility product of the order of 10". As for the KCl-NaCl-CaCl2 melt, the solubiUty product value should also be close to 1. On the contrary, most metal oxides slightly soluble in the KCl-NaCl melt were shown by Shapoval, Makogon and Pertchik to remain only slightly soluble in KCl-LiCl eutectic. Moreover, these oxides (NiO, CoO) are dissociated incompletely under these conditions. ... 

The metal oxide solubilities in the chloride-bromide sequence were shown in our papers to considerably decrease. For example, strontium oxide, which is referred to as moderately soluble in low-acidic chloride melts, becomes slightly soluble in the bromide melt. Calcium and cadmium oxides slightly soluble in chloride melts become practically insoluble in molten bromides. The basic properties of BaO in the bromide melt essentially weaken, and degree of its dissociation, in the saturated solution in molten bromide, considerably diminishes. 

Arsenic(III) oxide is slightly soluble in water, giving a solution with a sweetish taste—but as little as 0.1 g can be a fatal dose (The antidote is freshly-precipitated iron(III) hydroxide.) The solution has an acid reaction to litmus, due to the formation of arsenic(III) acid ... 

When sulphur is melted viscosity changes occur as the temperature is raised. These changes are due to the formation of long-chain polymers (in very pure sulphur, chains containing about 100 (X)0 atoms may be formed). The polymeric nature of molten sulphur can be recognised if molten sulphur is poured in a thin stream into cold water, when a plastic rubbery mass known as plastic sulphur is obtained. This is only slightly soluble in carbon disulphide, but on standing it loses its plasticity and reverts to the soluble rhombic form. If certain substances, for example iodine or oxides of arsenic, are incorporated into the plastic sulphur, the rubbery character can be preserved. 

In its chemistry, cadmium exhibits exclusively the oxidation state + 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 Of the halides, cadmium-... 

Formates. lron(Il) formate dihydrate [13266-734], Fe(HC02)2 2H20, is a green salt which can be prepared from iron(Il) sulfate and sodium formate in an inert atmosphere. The compound is slightly soluble in water and fairly resistant to air oxidation. The anhydrous salt [3047-594] is known. 

Tris(2,4-pentanedionato)iron(III) [14024-18-1], Fe(C H202)3 or Fe(acac)3, forms mby red rhombic crystals that melt at 184°C. This high spin complex is obtained by reaction of iron(III) hydroxide and excess ligand. It is only slightly soluble in water, but is soluble in alcohol, acetone, chloroform, or benzene. The stmcture has a near-octahedral arrangement of the six oxygen atoms. Related complexes can be formed with other P-diketones by either direct synthesis or exchange of the diketone into Fe(acac)3. The complex is used as a catalyst in oxidation and polymerization reactions. 

Nickel Carbonate. Nickel carbonate [3333-67-3], NiCO, is a light-green, rhombic crystalline salt, density 2.6 g/cm, that is very slightly soluble in water. The addition of sodium carbonate to a solution of a nickel salt precipitates an impure basic nickel carbonate. The commercial material is the basic salt 2NiCo2 3Ni(OH)2 4H20 [29863-10-3]. Nickel carbonate is prepared best by the oxidation of nickel powder in ammonia and CO2. Boiling away the ammonia causes precipitation of pure nickel carbonate (32). 

A fourth alkalinity control additive is magnesium oxide [1309A8A], which is used in clay-free polymer-base fluids (47). Magnesium oxide provides an alkaline environment and, as it is only slightly soluble, also has a buffering effect. It enhances the thermal stabHity of polymer solutions by preventing a pH decrease to neutral or slightly acidic conditions at elevated temperatures. It is mainly appHed in completion or workover operations where clay-free acid-soluble fluids are desired. 

Tetrasilver tetroxide is a powerful oxidizer for sanitizing swimming pools, hot tubs, and industrial cooling system waters (see Water, treatment of SWIMMINGPOOLS, SPAS, AND HOT tubs). This oxide is slightly soluble and its dissociation into silver ions is enhanced by the addition of the oxidizer KgSgOg. Bivalent and trivalent silver disinfectants have been shown to be from 50 to 200 times more effective as sanitizers than monovalent silver compounds. 

Physical Properties. Sodium metabisulfite (sodium pyrosulfite, sodium bisulfite (a misnomer)), Na2S20, is a white granular or powdered salt (specific gravity 1.48) and is storable when kept dry and protected from air. In the presence of traces of water it develops an odor of sulfur dioxide and in moist air it decomposes with loss of part of its SO2 content and by oxidation to sodium sulfate. Dry sodium metabisulfite is more stable to oxidation than dry sodium sulfite. At low temperatures, sodium metabisulfite forms hydrates with 6 and 7 moles of water. The solubiHty of sodium metabisulfite in water is 39.5 wt % at 20°C, 41.6 wt % at 40°C, and 44.6 wt % at 60°C (340). Sodium metabisulfite is fairly soluble in glycerol and slightly soluble in alcohol. 

Tungsten pentachlofide [13470-13-8], WCl, mp 243°C, bp 275.6°C, is a black, crystalline, deHquescent soHd. It is only slightly soluble in carbon disulfide and decomposes in water to the blue oxide, 200 2. Magnetic properties suggest that tungsten pentachlofide may contain trinuclear clusters in the soHd state, but this stmcture has not been defined. Tungsten pentachlofide may be prepared by the reduction of the hexachloride with red phosphoms (9). 

The gels precipitated as described above are not useful in ion-exchange systems because their fine size impedes fluid flow and allows particulate entrainment. Controlled larger-sized particles of zirconium phosphate are obtained by first producing the desired particle size zirconium hydrous oxide by sol—gel techniques or by controlled precipitation of zirconium basic sulfate. These active, very slightly soluble compounds are then slurried in phosphoric acid to produce zirconium bis (monohydrogen phosphate) and subsequently sodium zirconium hydrogen phosphate pentahydrate with the desired hydrauhc characteristics (213,214). 

Antimony trioxide is insoluble in organic solvents and only very slightly soluble in water. The compound does form a number of hydrates of indefinite composition which are related to the hypothetical antimonic(III) acid (antimonous acid). In acidic solution antimony trioxide dissolves to form a complex series of polyantimonic(III) acids freshly precipitated antimony trioxide dissolves in strongly basic solutions with the formation of the antimonate ion [29872-00-2] Sb(OH) , as well as more complex species. Addition of suitable metal ions to these solutions permits formation of salts. Other derivatives are made by heating antimony trioxide with appropriate metal oxides or carbonates. 

Because the sdv er oxide electrode is slightly soluble in the potassium hydroxide electroltye the separator is of a barrier type to minimize silver... 

Copper(I) chloride is insoluble to slightly soluble in water. SolubiUty values between 0.001 and 0.1 g/L have been reported. Hot water hydrolyzes the material to copper(I) oxide. CuCl is insoluble in dilute sulfuric and nitric acids, but forms solutions of complex compounds with hydrochloric acid, ammonia, and alkaU haUde. Copper(I) chloride is fairly stable in air at relative humidities of less than 50%, but quickly decomposes in the presence of air and moisture. 

The hydrolysis (which in the case of Fe produces acidic solutions) is virtually absent, and in aqueous solution the addition of C03 does not result in the evolution of CO2 but simply in the precipitation of white FeC03. The moist precipitate oxidizes rapidly on exposure to air but in the presence of excess CO2 the slightly soluble Fe(HC03)2 is formed. It is the presence of this in natural underground water systems, leading to the production of FeC03 on exposure to air, followed by oxidation to iron(III) oxide, which leads to the characteristic brown deposits found in many streams. 

Propylene oxide is similar in its structure to ethylene oxide, but due to the presence of an additional methyl group, it has different physical and chemical properties. It is a liquid that boils at 33.9°C, and it is only slightly soluble in water. (Ethylene oxide, a gas, is very soluble in water). 

Several immersion treatments using solutions containing chromates have been developed for aluminium. It is not always clear to what extent the films formed can properly be called chromate films, i.e. films containing a substantial amount of a slightly soluble chromium chromate, but even if the film consists largely of aluminium oxide or hydroxide or other salt with chromate physically absorbed, it will still provide a reservoir of soluble chromate at the metal surface. Treatments fall into two classes alkaline and acid. The latter are of more recent development. 

The "arsenic poison" referred to in true-crime dramas is actually the oxide of arsenic, As203, rather than the element itself. Less than 0.1 g of this white, slightly soluble powder can be fatal. The classic symptoms of acute arsenic poisoning involve various unpleasant gastroin-... 

Magnesium (eighth most abundant element) is found principally as Mg+2 ion in salt deposits, particularly as the slightly soluble carbonate, MgC03, and also in sea water. The element is oxidized by atmospheric oxygen and is not found in an uncombined state in nature. 

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