Mixtures of strong electrolytes

Idzikowski, S. (1973) Adsorption of inorganic ions on iron(III) oxide from mixtures of strong electrolytes. IV. Adsorption of silver, cupric and aluminium sulphate in presence of indifferent electrolyte. Rocz. Chem. 231-238... 

Formalism According to Pitzer. The most common method for the evaluation of the activity and osmotic coefficients of an electrolyte in a binary mixture of strong electrolytes with a common ion is by Scatchard s Equations (23), the McKay-Perring treatment (24), Mayers Equations... 

Electrolyte Mixtures. The calculation of the solubility of mixtures of strong electrolytes requires knowledge of the thermodynamic solubility product for all species that can precipitate and requires using an activity coefficient calculation method that takes into account ionic interactions. These techniques are well described in Zemaitis et al. (1986), however, we will discuss a simple case in this section. 

Onsager L, Fuoss RM (1932) Irreversible processes in electrolytes. Diffusion, conductance and viscous flow in arbitrary mixtures of strong electrolytes. J Phys Chem 36 2689-2778... 

An alternative way to describe the apparent molar volume of mixtures of strong electrolytes is by means of the multi-component form of the Pitzer equation (2.24). For a mixture of two 1 1 electrolytes with one common ion the expression reduces to (Corti and Svarc, 1995)... 

Ion-exchange processes can be differentiated by assignment to one of two groups Group I replacement of ions of one kind by ions of another, for example, purification of nonelectrolytes or weak electrolytes firom strong electrolytes, softening and demineralization of water, recovery of substances from solutions, etc. Group II separation of mixtures of dissolved electrolytes. 

Three systems were selected for examination, namely the solubilities of oxygen, carbon dioxide, and methane in water -1- sodium chloride. An accurate semiempirical equation [64] was used to express the composition dependence of the osmotic coefficient in water-r sodium chloride. The results of the calculations are presented in Fig. 1 and Table 1. One can see that Eq. (26) provides an accurate correlation for the gas solubility in solutions of strong electrolytes. In addition, the fluctuation theory allows one to use the experimental solubility data to examine the hydration in water (l)-gas (2)-cosolvent (3) mixtures. 

Furthermore, it was necessary to remodel completely the remaining contents. First the theoretical portion had to be extended considerably. In all acid-base equilibria, activities and not concentrations determine the equilibrium conditions. Therefore, from a practical viewpoint, a summarizing description of the modern theory of strong electrolytes and of the activity concept is indispensable, especially since otherwise phenomena such as influence of dilution on the pH of a buffer mixture, or the salt vcrror of indicators, etc. have no quantitative explanation. 

Eq. (B.l) will allow fairly accurate estimates of the aetivity coefficients in mixtures of electrolytes if the ion interaction coefficients are known. Ion interaction coefficients for simple ions can be obtained from tabulated data of mean activity coefficients of strong electrolytes or from the corresponding osmotic coefficients. Ion interaction coefficients for complexes can either be estimated from the charge and size of the ion or determined experimentally from the variation of the equilibrium constant with the ionic strength. 

When the mixture contains strong electrolytes of the same ion type (say all univalent or all bivalent) then the activity coefficient of a given electrolyte is very dilute solutions is the same in all solutions of the same total normality. In more concentrated solutions, the specific-character of the ions influences the activity coefficient. 

Ionic surfactants with only one alkyl chain are generally extremely hydrophilic so that strongly curved and thus almost empty micelles are formed in ternary water-oil-ionic surfactant mixtures. The addition of an electrolyte to these mixtures results in a decrease of the mean curvature of the amphiphilic film. However, this electrolyte addition does not suffice to drive the system through the phase inversion. Thus, a rather hydrophobic cosurfactant has to be added to invert the structure from oil-in-water to water-in-oil [7, 66]. In order to study these complex quinary mixtures of water/electrolyte (brine)-oil-ionic surfactant-non-ionic co-surfactant, brine is considered as one component. As was the case for the quaternary sugar surfactant microemulsions (see Fig. 1.9(a)) the phase behaviour of the pseudo-quaternary ionic system can now be represented in a phase tetrahedron if one keeps temperature and pressure constant. 

Macedo, E.A., Skovborg, P. and Rasmussen, P. (1990) Calculations of phase equilibria for solutions of strong electrolytes in solvent-water mixtures. Chemical Engineering Science, 45, 875-882. 

In fact, two-phase electrolytic media do not constitute practical systems for electrochemistry, and homogeneous benzene-acid solutions appeared preferable. These were achieved by using various mixtures of strong acids and superacids. 

Mixtures of strong and associating electrolytes have been described also [36, 38]. For mixed electrolytes a natural extension of eqs 5.38 and 5.39 is... 

Boyd GE (1974) Thermodynamic properties of strong electrolyte strong polyelectrolyte mixtures at 25°C. In Selegny E (ed) Polyelectrolytes. D. Reidel, Boston, pp 135 155... 

THERMODYNAMIC PROPERTIES OF STRONG ELECTROLYTE -STRONG POLYELECTROLYTE MIXTURES AT 25°C [1]... 

The composition of the electrolyte is quite important in controlling the electrolytic deposition of the pertinent metal, the chemical interaction of the deposit with the electrolyte, and the electrical conductivity of the electrolyte. In the case of molten salts, the solvent cations and the solvent anions influence the electrodeposition process through the formation of complexes. The stability of these complexes determines the extent of the reversibility of the overall electroreduction process and, hence, the type of the deposit formed. By selecting a suitable mixture of solvent cations to produce a chemically stable solution with strong solute cation-anion interactions, it is possible to optimize the stability of the complexes so as to obtain the best deposition kinetics. In the case of refractory and reactive metals, the presence of a reasonably stable complex is necessary in order to yield a coherent deposition rather than a dendritic type of deposition. 

Triphenylmethyl sodium and triphenylmethyl potassium conduct in liquid ammonia although they slowly react with that solvent.887 888 When the liquid ammonia is allowed to evaporate from a solution of triphenylmethyl sodium in ammonia, the residue is a colorless mixture of sodamide and triphenylmethane. The sodium-tin and sodium-germanium compounds analogous to sodium triphenylmethide are also strong electrolytes in liquid ammonia. Sodium acetylide in liquid ammonia is dissociated to about the same extent as sodium acetate in water.889... 

Nitrotoluene may be oxidized by means of strong nitric acid,2 chromic acid mixture,3 or permanganates.4 Electrolytic oxidation 5 has also been proposed. The procedure given above involves the use of chromic acid mixture, but, owing to a change in the concentration of sulfuric acid, the time of reaction is greatly shortened and the preparation is thus considerably improved. 

The basicity or acidity of the electrolyte, and in particular, the methanol concentration, strongly influences the product distribution. With an equimolar mixture of cyclohexene and methanol in tetrahy-drofuran, 81% of 3-methoxycyclohexene... 

Controlled one-electron reductions transform l,2,3,4-tetraphenyl-l,3-cyclopentadiene or 1,2,3, 4,5-pentaphenyl-l,3-cyclopentadiene into mixtures of the dihydrogenated products and the corresponding cyclopentadienyl anions (Famia et al. 1999). The anion-radicals initially formed are protonated by the substrates themselves. The latter are thermodynamically very strong acids because of their strong tendency to aromatization. As with the cyclopentadiene anion-radicals, they need two protons to give more or less stable cyclopentadienes. The following equations represent the initial one-electron electrode reduction of l,2,3,4,5-pentaphenyl-l,3-cyclopentadiene (CjHAtj) and explains the ratio and the nature of the products obtained at the expense of the further reactions in the electrolytic pool ... 

SOLUTION and MIXTURE - There is some confusion between these two terms in geological literature. According to the I.U.P. A.C. (International Union for Pure and Applied Chemistry), the term mixture must be adopted whenever all components are treated in the same manner , whereas solution is reserved for cases in which it is necessary to distinguish a solute from a solvent. This distinction in terminology will be more evident after the introduction of the concept of standard state. It is nevertheless already evident that we cannot treat an aqueous solution of NaCl as a mixture, because the solute (NaCl) in its stable (crystalline) state has a completely different aggregation state from that of the solvent (H2O) and, because NaCl is a strong electrolyte (see section 8.2), we cannot even imagine pure aqueous NaCl. 

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