Aqueous solutions and oxides

The interaction between ammonia in an aqueous solution and oxide is very exothermic and has to be managed carefully. If ammonia is in the gaseous state, the exothermicity of the interaction causes incandescence of the oxide, causing serious accidents. 

Relaxation studies have shown that the attachment of an ion to a surface is very fast, but the establishment of equilibrium in wel1-dispersed suspensions of colloidal particles is much slower. Adsorption of cations by hydrous oxides may approach equilibrium within a matter of minutes in some systems (39-40). However, cation and anion sorption processes often exhibit a rapid initial stage of adsorption that is followed by a much slower rate of uptake (24,41-43). Several studies of short-term isotopic exchange of phosphate ions between aqueous solutions and oxide surfaces have demonstrated that the kinetics of phosphate desorption are very slow (43-45). Numerous hypotheses have been suggested for this slow attainment of equilibrium including 1) the formation of binuclear complexes on the surface (44) 2) dynamic particle-particle interactions in which an adsorbing ion enhances contact adhesion between particles (43,45-46) 3) diffusion of ions into adsorbents (47) and 4) surface precipitation (48-50). 

Leaching of ions and break-down of silicates During leaching of a mineral an ion is removed from a site in a crystal structure to an aqueous phase. Most transition metal ions are present in six-coordinated sites in silicate minerals and exist in aqueous solutions as hexahydrated ions, [A/(H20)6]"+. The crystal field splittings summarized in table 2.5 indicate that CFSE s of ions in aqueous solutions and oxide structures are comparable,... 

At 10 kGy and without excipients, the loss of human insulin in aqueous solutions is almost complete. Addition of radio-protecting excipients (free radicals scavengers) and cryo-irradiation allowed to decrease insulin degradation. The best radio-protector used was ascorbic acid in aqueous solution and oxidized glutathione in the frozen solutions. 

Water-reactive chemicals Store in dry, cool, location protect from water from fire sprinkler. Sodium metal, potassium metal, lithium metal, lithium aluminum hydride Separate from all aqueous solutions and oxidizers... 

Structure and Acidity in Aqueous Solutions and Oxide-Water... 

Bickmore BR (2013) Structure and acidity in aqueous solutions and oxide-water interfaces ... 

Alexandridis P and Hatton T A 1995 Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) blook oopolymer surfaotants in aqueous solutions and at interfaoes thermodynamios, struoture, dynamios, modeling Colloids Surf. A 96 1-46... 

The actinide elements exhibit uniformity in ionic types. In acidic aqueous solution, there are four types of cations, and these and their colors are hsted in Table 5 (12—14,17). The open spaces indicate that the corresponding oxidation states do not exist in aqueous solution. The wide variety of colors exhibited by actinide ions is characteristic of transition series of elements. In general, protactinium(V) polymerizes and precipitates readily in aqueous solution and it seems unlikely that ionic forms ate present in such solutions. 

In aqueous solution, OF2 oxidizes HCl, HBr, and HI (and thek salts), Hberating the free halogens. Oxygen difluoride reacts slowly with water and a dilute aqueous base to form oxygen and fluorine. The rate of this hydrolysis reaction has been determined (23). 

Perchlorates. Iron(II) perchlorate hexahydrate [13922-23-8], Fe(C10 2 6H20, is prepared by dissolving iron in cold, dilute perchloric acid or by dissolving FeS in perchloric acid. It crystallizes in hygroscopic, light green hexagonal prisms which are stable in dry air and extremely soluble (0.978 g/mL H2O at 0°C) in water and alcohol. It is susceptible to air oxidation in aqueous solution and decomposes above 100°C. Yellow iron(III) perchlorate... 

Plutonium(III) in aqueous solution, Pu " ( 4)> is pale blue. Aqueous plutonium(IV) is tan or brown the nitrate complex is green. Pu(V) is pale red-violet or pink in aqueous solution and is beUeved to be the ion PuO Pu(VI) is tan or orange in acid solution, and exists as the ion PuO. In neutral or basic solution Pu(VI) is yellow cationic and anionic hydrolysis complexes form. Pu(VII) has been described as blue-black. Its stmcture is unknown but may be the same as the six-coordinate NpO (OH) (91). Aqueous solutions of each oxidation state can be prepared by chemical oxidants or reductants... 

Relative rates of eompetitive reaetions ehemieal oxidation, lysing baeteria, decomposition of ozone in aqueous solutions, and so on. 

Sulfa-Check process uses sodium nitrite (NaN02) in aqueous solution to oxidize H2S to sulfur. This process was developed and patented by NL Treating Chemicals and is now a product of Exxon Energy Chem-... 

The first of these types is most familiarly represented by the hexaaquo ion which is present in acidic aqueous solutions and, in the solid state, in the alum CsTi(S04)2.12H20. In fact few other neutral ligands besides water form a [TiLg] + complex. Urea is one of these few and [Ti(OCN2H4)g]l3, in which the urea ligands coordinate to the titanium via their oxygen atoms, is one of the compounds of titanium(III) most resistant to oxidation. 

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