Study of Activity Coefficient of Hydrochloric Acid in 2-Propanol-Water Mixture by Electromotive Force Measurement Method

This paper is mainly focusing on the determination of mean molal activity coefficient of HCl in aqueous acidic medium. The present investigations have been carried out to determine the activity coefficients of hydrochloric acid in 2-propanol water mixture solutions under various conditions to study the ion solvent interactions in different temperatures. The standard molar potential Em0 of the cell; Pt; H2(g) /HCl(m) x% 2-propanol; Hg2Cl2(S)/Hg have been determined in 10%; 20% and 30% (w/w) of 2-Propanol-water mixture solution at three different temperatures 308K, 313K and 318K and molality ranging from 0.005 to 0.1 mol Kg-1. Eo of the cell can be computed by modified Davies equation as below, where K= 2.3026(RT/F), A΄ = appropriate Debye-Hückel constant and Mean molal activity coefficient, The mean molal activity coefficients of hydrochloric acid in aqua organic media and temperature are also computed. The primary ion-solvent effects and the secondary ion-solvent effects are also reported.