Electrical Conductivity and Thermodynamics of the Process of Ionic Association of Ionic Liquids 1-Alkylpyridinium Bromotrichloroferrates in Acetone

The electrical conductivity of 1-alkylpyridinium ionic liquids with the bromotrichloroferrate anion in acetone in the temperature range of 298–318 K has been studied. According to the obtained conductometric data, the ion association constants (Ka), the limiting molar electrical conductivities (λ0), and the Gibbs energy of association ( Δ G_a⁰ ) in solutions were calculated for the studied compounds by the Lee–Wheaton method. The values of enthalpy ( Δ H_a⁰ ) and entropy ( Δ S_a⁰ ) of association are obtained from the temperature dependence of the equivalent electrical conductivity (EC). The Walden–Pisarzhevsky product was calculated for all the studied compounds. The activation energies (Eκ) of the specific electrical conductivity are calculated. Conclusions are drawn regarding the influence of the structure of 1-alkylpyridinium bromotrichloroferrates on the thermodynamic parameters of association and the activation energy of electrical conductivity in acetone solutions.