Electrolyte in binary mixture

Conductance and Ionic Association of Several Electrolytes in Binary Mixtures Involving Sulfolane (TMS) and Protic Solvents... 

Conductometric and spectrophotometric behavior of several electrolytes in binary mixtures of sulfolane with water, methanol, ethanol, and tert-butanol was studied. In water-sulfolane, ionic Walden products are discussed in terms of solvent structural effects and ion-solvent interactions. In these mixtures alkali chlorides and hydrochloric acid show ionic association despite the high value of dielectric constants. Association of LiCl, very high in sulfolane, decreases when methanol is added although the dielectric constant decreases. Picric acid in ethanol-sulfolane and tert-butanol-sulfolane behaves similarly. These findings were interpreted by assuming that ionic association is mainly affected by solute-solvent interactions rather than by electrostatics. Hydrochloric and picric acids in sulfolane form complex species HCl and Pi(HPi). ... 

T he determination of the activity coefficient of an electrolyte in binary mixtures of another electrolyte with a common ion has prompted considerable interest, both in the development of the underlying theory, as well as precise experimental measurements. This kind of study is useful in applications that involve metallurgical and biological systems. The ion interaction parameters (doublet and triplet, among others) responsible for an understanding of the effects of cation size on the thermodynamic... 

Aqueous solutions of electrolytes that dissociate into ions have been and are studied so extensively that it is natnral to enquire about the solutions of electrolytes in binary mixtures of water and cosolvents. Mixtures of nonaqueous solvents among themselves, although important for other purposes, have not received much attention when solutions of electrolytes are concerned. Therefore, this section deals only with binary mixtnres of water with cosolvents. Many of the solvents on the list are miscible with water at all proportions, whereas others exhibit limited, even rather low mutual solubility at ambient conditions. For these cases, solubility of water in the solvent, is larger than that of the solvent in water, x, on the mole fraction scale. Conversion to (approximate) values of the solubility on the molar scale is according to ... 

Electrolytic conductivity has also been measured in many binary systems. " Although data on conductivities in binary mixtures are very useful for practical purposes, the information from such data alone is limited from the viewpoint of elucidation of the mechanism. For example, the empirical Markov rule is well known for the electrical conductivity of binary mixtures. However, many examples have been presented where this rule does not hold well. 

Figure 12.4 Equilibrium absorption isotherms at 34 °C and rate of dyeing curves at 40 °C for Cl Direct Blue 1 on viscose in the presence of electrolytes singly and in binary mixtures [70]...

Thermodynamics of Preferential Solvation of Electrolytes in Binary Solvent Mixtures... 

This example clearly demonstrates, that with respect to a micelle-like association of ionic polysurfactants, the more complex ternary mixtures containing an electrolyte must be used to avoid extended polymer chains. This is in contrast to non-ionic polysurfactants, in which these effects do not occur in binary mixtures. 

A logical division is made for the adsorption of nonelectrolytes according to whether they are in dilute or concentrated solution. In dilute solutions, the treatment is very similar to that for gas adsorption, whereas in concentrated binary mixtures the role of the solvent becomes more explicit. An important class of adsorbed materials, self-assembling monolayers, are briefly reviewed along with an overview of the essential features of polymer adsorption. The adsorption of electrolytes is treated briefly, mainly in terms of the exchange of components in an electrical double layer. 

Binary Electrolyte Mixtures When electrolytes are added to a solvent, they dissociate to a certain degree. It would appear that the solution contains at least three components solvent, anions, and cations, if the solution is to remain neutral in charge at each point (assuming the absence of any applied electric potential field), the anions and cations diffuse effectively as a single component, as for molecular diffusion. The diffusion or the anionic and cationic species in the solvent can thus be treated as a binary mixture. 

Frank, H. S. Evans, M. W. (1945). Entropy in binary liquid mixtures partial molal entropy in dilute solutions structure and thermodynamics in aqueous electrolytes. Journal of Chemical Physics, 13, 507-32. 

Methodically, there is no great difference between measuring the mean activity coefficient in a solution of one electrolyte and measuring this quantity in a mixture of electrolytes. Binary mixtures have been studied most extensively. If osmotic methods are used, then the coefficients ocx and... 

An application to one binary mixture of a volatile electrolyte and water will illustrate the choice of parameters H and K, an approach is proposed to represent the vapor-liquid equilibrium in the whole range of concentration. Ternary mixtures with one acid and one base lead to the formation of salts and high ionic strengths can be reached. There, it was found useful to take into account... 

Electrolytic (coukxnetric) hygrometers The quantity of electricity required to carry out a chemical reaction is measured. The principle is based upon Faraday s law of electrolysis. Water is absorbed on to a thin film of dessicant (e.g. P2O5) and electrolysed. The current required for the electrolysis varies according to the amount of water vapour absorbed. The current depends also upon the flowrate. Capable of high precision. Used in the range 1000 to 3000 ppm of water by volume. Somewhat complicated procedure. Recombination of products to water is necessary after electrolysis. Density, pressure and flowrates have to be maintained precisely. Contamination can poison the cell. It is ideal for binary mixtures but is of limited range. Suitable for on-line operation. 

Dholabhai PD, Parent JS, Bishnoi PR (1997) Equilibrium conditions for hydrate formation from binary mixtures of methane and carbon dioxide in the presence of electrolytes, methanol and ethylene glycol. Fluid Phase Equilibria 141 235-246... 

Thus, the Maxwell-Stefan diffusion coefficients satisfy simple symmetry relations. Onsager s reciprocal relations reduce the number of coefficients to be determined in a phenomenological approach. Satisfying all the inequalities in Eq. (6.12) leads to the dissipation function to be positive definite. For binary mixtures, the Maxwell-Stefan dififusivity has to be positive, but for multicomponent system, negative diffusivities are possible (for example, in electrolyte solutions). From Eq. (6.12), the Maxwell-Stefan diffusivities in an -component system satisfy the following inequality... 

Thus generally, for liquids D°AB D°BA. Different techniques with which to estimate the infinite dilution diffusion coefficient are described by Reid et al. [31]. Various correlation s (valid for an arbitrary composition of a binary mixture and for electrolytes) are also given. In the Wilke-Chang correlation for D°AB the effect of temperature has been accounted for by assuming D°AB — T. Although this approximation may be valid over small temperature ranges, it is usually preferable to assume that... 

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