In this article we present a model for correlating dynamic and kinematic viscosities of liquid mixtures, which is based on Eyring's absolute rate theory for liquid viscosity and the UNIQUAC equation. The proposed model involves the concept of ideal viscosity and uses the UNIQUAC equation to represent the deviation from ideal behavior. The expression adopted to describe the ideal term viscosity has been chosen after a thorough investigation of the performance of different equations previously proposed in the literature. The correlation results have shown a strong dependence on the expression used to account for the ideal viscosity contribution. Besides size and shape parameters, for each pure component, the model requires only two adjustable parameters per binary system. The binary interaction parameters have been determined by fitting literature viscosity data. More than 350 binary systems, 4619 viscosity data points at 0.1 MPa, have been correlated using this model. The binary systems investigated are representative of different types of intermolecular interactions (e.g., nonpolar/nonpolar, nonpolar/polar, and polar/polar). The calculated values are in good agreement with the experimental ones. The overall average mean relative standard deviation of the correlations is 1.20%, which is comparable with those of other correlation models available in the literature.

In this article we present a new model for correlating dynamic viscosity of binary strong electrolyte solutions. The proposed model is based on Eyring's absolute rate theory and the Debye−Hückel model for calculating the excess (electrostatic) free energy of activation of the viscous flow. In the present model we consider that the free energy of activation of the viscous flow as being the same as the appropriate thermodynamic free energy used for calculating equilibrium properties of the electrolyte solution. Modifications of Eyring's absolute rate theory must be performed to take into account the solvent as a continuous medium, as considered in the Debye−Hückel theory. This is accomplished by means of the osmotic-pressure framework for solutions. In this framework one adopts a thermodynamic free energy, which is considered as a function of the absolute temperature, pressure, number of moles of the solute species, and chemical potential of the solvent. The proposed model contains two adjustable parameters that have been fitted by means of experimental viscosity data of the literature. The total number of 21 binary electrolyte systems (at 0.1 MPa and 25 °C) with different solvents (water, methanol, ethanol, and 1-butanol) have been studied. The calculated viscosity values are in good agreement with the experimental ones. The overall average mean relative standard deviation is 0.52%.

The dissolution of copper in 1M chloride solution was studied by steady‐state (current‐voltage curves for various disk rotation rates) and transient [frequency analysis of the electrochemical and electrohydrodynamical (EHD) impedance] measurements. The anodic polarization curves have presented one region of mixed kinetic and another of mass‐transport control characterized by a current plateau. The limiting current is a Ω1/2 function throughout the whole range of rotation rates. From the EHD impedance diagrams observed below the anodic plateau, it was shown that the limitation by mass transport is due to CuCl2− . On the current plateau, the presence of two time constants on the EHD impedance diagram and the reductibility of the curves have been attributed to the existence of a salt layer covering the surface, the rate of formation of this layer being identical to the rate of dissolution. A layer model has been developed.

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is clear that there is a strong (111) preferred orientation for Cu plated from the cyanide bath, which is reduced by 70% via interspersion of the Ag layers (at the 6.5% level).A very significant finding from Table II1 is that Ag displacement deposition apparently occurs epitaxially and exclusively on Cu(lll) planes. Only the (111) orientation is detected for Ag in the as-deposited multilayer, and the diffracted x-ray intensity is 6.6% of that for Cu(lll) in the same specimen. Assuming that (111) diffraction is equivalent for Cu and Ag, which should be a reasonable approximation for metals having the same crystal structure, this percentage should reflect the concentration of Ag in the displacement layers, which is 5.5%. In view of the limitations on such an assumption, the agreement is good, suggesting that nearly 100% of the Ag grows epitaxially on Cu(111) planes.