Electrical Conductivity and Thermodynamics of Ion Association of Ammonium Ionic Liquids in Acetone

The electrical conductivity of a number of tetraalkylammonium ionic liquids with tetrafluoroborate anion has been studied in acetone in the temperature range 298–313 K. Based on the obtained conductometric data for the compounds under study, the Lee–Wheaton method has been used to calculate the ion association constants (Ka), limiting molar electrical conductivities (λ0), and Gibbs association energy (ΔG0) in solutions. From the temperature dependence of equivalent electrical conductivity, the values of association enthalpy (ΔH0) and entropy (ΔS0) have been calculated. For all studied compounds, the Walden–Pisarzhevsky product has been calculated. Conclusions are drawn about the influence of the structure of the studied ionic liquids on the thermodynamic parameters of association in acetone solutions.