Water in aqueous solutions

Halohydrin fonnation, as depicted in Figure 6.13, is mechanistically related to halogen addition to alkenes. A halonium ion intennediate is fonned, which is attacked by water in aqueous solution. 

For reactions involving a nearly pure liquid or solid (often the case for water in aqueous solutions) G is given by the following expression, where X is the mole fraction of the liquid ... 

Transients from Water in Aqueous Solution. 1. Hydrated Electron. NSRDS-NBS 43, National Bureau of Standards, Washington, D.C. 

Anbar, M., Bambaneck, M., and Ross, A. B. (1973), Selected Specific Rates of Reactions of Transients from Water in Aqueous Solution. I. Hydrated Electron, NSRDS-NBS 43, National Bureau of Standards, Washington, D. C. 

Formaldehyde is normally a gas at room temperature, but dissolves in water. In aqueous solution, formaldehyde exists almost entirely as the... 

Hydrogen bonds between water molecules provide the cohesive forces that make water a liquid at room temperature and that favor the extreme ordering of molecules that is typical of crystalline water (ice). Polar biomolecules dissolve readily in water because they can replace water-water interactions with more energetically favorable water-solute interactions. In contrast, nonpolar biomolecules interfere with water-water interactions but are unable to form water-solute interactions— consequently, nonpolar molecules are poorly soluble in water. In aqueous solutions, nonpolar molecules tend to cluster together. 

To measure the effect of the presence of ions on the hydrogen-bond structure of bulk water, we studied the concentration dependence of the orientational relaxation of bulk water in aqueous solutions of Mg(C104)2. We chose Mg(C104)2 because Mg2+ is considered to be a strong structure-making ion the viscosity of 1 M Mg(C104)2 is about 30 %... 

An early treatment of the problem of calculating effective concentrations was to consider the concentration of an intramolecular group to be approximately the same as that of water in aqueous solution, since a molecule in solution is completely surrounded by water.22 This gives an upper limit of 55 M for effective concentration, equivalent to 34 J/deg/mol (8 cal/deg/mol) of entropy. That figure does represent the probability of two molecules being next to each other in solution. But, as soon as the two molecules are tightly linked, there is a large loss of entropy. A loose transition state may, perhaps, be interpreted as two molecules that are in close juxtaposition but that retain considerable entropic freedom. 

The Pt/Ti02 photocatalyst can theoretically split water in aqueous solution, because Ti02 has the appropriate conduction band and valence band for H2 and 02 evolution, respectively. However, there are several reasons why the water splitting can not occur over Pt/Ti02 on carbonate-free solutions. Fig. 14.6(a) shows the... 

The sulfate is sparingly soluble in water. In aqueous solution, it hydrolyzes much more slowly than does the corresponding cw-dichloro complex with respect to substitution of its first chloride by water. The visible spectrum in water showed (e,X )max (87.9, 516) (72,375). This spectrum is in fair agreement with that reported in the literature7 for the pure chloride salt, (e,X )max (85.5, 516). 

Farhataziz and A.B. Ross. 1977. Selected specific rates of reactions of transients from water in aqueous solution. III. Hydroxyl and perhydroxyl radical. National Bureau of Standards NSRDS-NBS59. Washington, DC. 

Ross AB. Selected specific rates of reaction of transients from water in aqueous solution. Hydrated electron, supplemental data. Natl Stand Ref Data Ser, Nat Bur Stand (US) 1973 43(Suppl) 43 pp. 

Weber W, Ford PC (1986) Photosubstitution reactions of the ruthenium(II) arene complexes Ru(r 6-arene)L32+ (L = ammonia or water) in aqueous solution. Inorg Chem 25 1088-1092... 

Figure 16 shows the mixing curve between copolymers containing AA and RNA in water. In aqueous solution, purine and pyrimidine bases in co-... 

The icosahedral cluster model1,2 offers a structure on which large molecules can be mapped in order to investigate their interaction with water within a three-dimensional hydrogen-bonded network, and here offers new insights into the ways fullerene and polyoxomolybdate molecules interact with water in aqueous solution. 

FIGURE 10.1 Organosilane coupling agents react with water in aqueous solutions to form hydrolyzed silanes that react with the surface of inorganic fillers or the adherend. The bound silane polymerizes, building up layers outward, with the organic functionality oriented to the resin matrix.3... 

The interaction between dissolved ions and the dipole molecules of water in aqueous solutions is called - hydration. (See also - Born equation, -> Born-Haber cycle, -> Born-Mayer equation, -> hydrated ion, -> hydration number.)... 

Aluminum sulfate, A12(S04)3, is used to help clarify water. In aqueous solution, it is slightly acidic. 

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