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El-Hammamy et al. [16], measured the conductance of 1:1 s-acetylthiocholine salts ( Cl^-, Br^-, I^- and ClO₄^-) in water at different temperatures (25, 30, 35 °C) and the data were analyzed using Fuoss-Onsager equation. Values of Λ₀, K_A and α⁰ were obtained (solvation). It was found that Λ₀ and α⁰ increase, while K decrease with increasing the temperatures for all salts of s-acetylthiocholine according to electrostatic attraction theory. Thus from the plot of log Λ₀ vs. 1/T for s-acetylthiocholine halides and perchlorate in water at different temperatures, ΔES values have been evaluated, also ΔH⁰, ΔG⁰ and ΔS⁰ for salts. It was found that negative values of ΔH⁰, ΔG⁰ and ΔS⁰ in water at different temperatures; negative value of ΔH⁰ indicated that ion association processes were exothermic. The solvated radii were also increased with temperature indicating a higher solvation process due to increase in the electronic clouds around the solvated molecules as a result of an increase in their vibration and rotational motion. The limiting equivalent conductance and dissociation degree were also increased as the temperature increased, indicating higher solvation process [16]. The negative values of different thermodynamic parameters ΔH⁰, ΔG⁰ and ΔS⁰, for all salts under test in the used solvent, indicated exothermic association process with less energy-consuming and more stabilization [17]. While in [18], El-Hammamy et al. [18] measured the conductance of s-acetylthiocholine salts (Br^-, I^- and ClO₄^-) in acetonitrile at different temperatures (25, 30, 35, 40 °C) the data were analyzed using Fuoss-Onsager equation. The values of Λ₀, K_A and α⁰ (solvation) were obtained. It was found that Λ₀ and K_A increase with increasing the temperature. Thus from the plot of log Λ₀ vs. 1/T for each salt in acetonitrile solutions at different temperatures, ΔE_s(+ve) values have been evaluated, and also ΔH⁰, ΔG⁰ and ΔS⁰ all the salts. It was found that ΔH⁰ and ΔS⁰ are positive values at a particular temperatures but ΔG⁰ is negative. This is due to the solvation processes is less but association of ion increase with thermodynamic parameters. Endothermic solvation needs energy to break the bond around free ion and ion-pairs, i.e., endothermic solvation process was less energy consuming and more stabilized.