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 electrode potential E-0 of the cell Pt; H-2(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 308.15, 313.15 and 318.15 K and molality ranging from 0.005 to 0.1 mol kg(-1). E degrees of the cell is computed by modified Davies equation as below, E + klog m(H).m(cl) -(2kA root mu)/1+root mu = E degrees - k beta mu where k = 2.3026 (RT/ F), and A' = appropriate Debye-Huckel constant and mean molal activity coefficient, log gamma(i) = -(A'Z(i)(2)root mu)/1+root mu+beta(i)mu. The mean molal activity coefficients of hydrochloric acid in aqua organic media and temperature are also computed. The primary and secondary ion-solvent effects are also reported.