Electrical conductances of tetraalkylammonium iodides, R4NI (R = pentyl to heptyl) have been measured at 298.15 K in low-permittivity mixtures of 1,4-dioxane (ε = 2.21) and tetrahydrofuran (ε = 7.58). Minima in the conductometric curves (Λ versus √c) were observed for electrolyte concentrations dependent upon both the electrolyte and the binary solvent mixture. The conductance data have been analyzed by the Fuoss−Kraus theory of triple ions. A numerical evaluation of ion-pair and triple-ion formation constants (K P and K T ) was made, and the results have been discussed in terms of a molecular scale model.

Densities and viscosities were measured for binary mixtures of isoamyl alcohol with 2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol over the entire range of composition at 303.15 K, 313.15 K, and 323.15 K and ultrasonic speeds and refractive indices at 303.15 K under atmospheric pressure. From the experimental values of density, viscosity, ultrasonic speed, and refractive index, the values of excess molar volume (V E ), viscosity deviations ( η), deviations in isentropic compressibility ( K S ), and excess molar refraction ( R) have been calculated. The excess or deviation properties were found to be either negative or positive, depending on the molecular interactions and the nature of liquid mixtures.

No abstract

No abstract

Electrical conductances of tetraalkylammonium iodides, R4NI (R = butyl to heptyl), in different mass % (20 to 80) of carbon tetrachloride (CCl4) + nitrobenzene (PhNO2) have been measured at 298.15 K. Limiting molar conductances Λ0, association constants K A, and cosphere diameter R for ion pair formation in the mixed solvent mixtures have been evaluated using the Lee−Wheaton conductivity equation. However, the deviation of the conductometric curves (Λ versus √c) from linearity for the electrolytes in 80 mass % of CCl4 + PhNO2 indicated triple ion formation, and therefore corresponding conductance data have been analyzed by the Fuoss−Kraus theory of triple ions. Limiting ionic molar conductances λ0 ± have been calculated by the reference electrolyte method along with a numerical evaluation of ion pair and triple ion formation constants (K P ≈ K Aand K T); the results have been discussed in terms of solvent properties and configurational theory.