Thermodynamic Studies of Hydrochloric Acid in Propan-2-ol from Electromotive Force Measurements between 5 and 45°C

Abstract

The e.m.f. of the cell Pt, H2(g, 1 atm)| HCl(m), propan-2-ol | AgCl, Ag at 5°C intervals from 5 to 45°C for hydrochloric acid solutions in the range 0.005 to 0.1 mol kg–1 has been used to calculate (a) the standard e.m.f. of the cell at each temperature, (b) the mean molal activity coefficients of HCl at 25°C, (c) the primary medium effet, and (d) the thermodynamic transfer quantities, ΔG°t, ΔH°t, ΔS°t, and ΔC°pt for the transfer of HCl from water to propan-2-ol. The significance of the evaluated thermodynamic functions for the transfer process has been discussed in relation to the acid-base strength, as well as the structural features of the solvents (water and propan-2-ol).