This paper presents the results of density and viscosity measurements for glycerol solutions of KCl, NaCl, KBr, and KI at 25 °C. The apparent and partial molar volumes (V Φ and V 1) were calculated from the density data. The Debye−Hückel limiting law was assumed to be valid at low concentrations, and values of the molar volumes at infinite dilution were obtained by extrapolation. The viscosity data were analyzed by means of the Jones−Dole equation. The Kaminsky method, based on B K + = B Cl - , developed for the separation of the B-coefficients in aqueous solutions was used in glycerol. The ionic B-coefficients are discussed in terms of structure-making and structure-breaking properties of ions in glycerol. A comparison of molar volume data with viscosity data in glycerol shows that, as in aqueous solutions, the salt (NaCl) having the highest B-coefficient exhibits the smallest limiting apparent molar volume . Finally, the similarities of ion−solvent interactions in pure water with those in glycerol and the effects that the solutes seem to have on both solvents are discussed.

The electrical conductivities of solutions of salts (KCl, NaCl, KBr, NaBr, NaI, KI, and LiBr) in glycerol have been measured at three concentrations (approximately 0.01, 0.1, and 0.3 M) at 25 °C and at other temperatures from (3.37 to 42.24) °C in the case of KCl and NaCl. Values of the molar conductivity at infinite dilution were obtained by extrapolation using the conductance equation of Onsager. Using previously measured transference numbers for KCl and NaCl in glycerol, values of limiting Walden products for the individual alkali-metal and halide ions in glycerol have been derived and compared with those in aqueous and other alcohol solutions. The values for glycerol were the largest so far measured. The limiting ion conductivities, λ ∞ , obtained from experimental data were compared with those calculated applying the Boyd-Zwanzig theory. A modified Walden rule, Λ ∞ η p ) constant, is suggested as applicable in glycerol, the exponent p being less than unity and having a value down to 0.9. Finally, the temperature dependence of the Walden product for NaCl-and KCl-glycerol solutions is discussed.

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We present electrochemical impedance spectra made on gold alloy containing 30% silver electrodes of various roughnesses in aqueous perchlorate acid solution as supporting electrolyte in the absence and in the presence of mM of specifically adsorbed halide ions X (X = Br, at potentials where the dominant electrode process is the adsorption of the above anions. Efforts were mainly concentrated on the importance of surface preparation technique of the electrode and its influence on impedance spectra. Atomic scale inhomogeneities are introduced by mechanical treatment and can be decreased by annealing. Due to the annealing the double layer behaves as (almost) an ideal capacitance in the absence of specific adsorption though the surface roughness remains the same. A study of the related impedance behaviour in the presence of adsorbates even at very low concentrations (10 -4 M), revealed capacitance dispersion increasing with the extent of specific anion adsorption at the gold/silver surface.