THERMODYNAMICS OF MIXED ELECTROLYTES IN M IXED-SOLVENTS - SYSTEM OF HCL-NACL-TERT-C4H9OH-H2O FROM 5-DEGREES-C TO 45-DEGREES-C

The thermodynamic properties of system HCl-NaCl-tert.-C4H9OH-H2O was s tudied by emf measurement in the cells without liquid junction: Pt, H- 2(1.013 x 10(5)Pa)\HCl (m), tert.-C4H9OH (x), H2O (1-x)\AgCl-Ag (A) Pt , H-2(1.013 x 10(5)Pa)\HCl (m(A)), NaCl (m(B)), tert.-C4H9OH (x), H2O (1-x)\AgCl-Ag (B) at constant total ionic strength I=0.5, 1.0, 2.0 and 3.0mol. kg-1, from 5 to 45-degrees-C, where m(A) and m(B) are the mol alities of HCl and NaCl, respectively, x is the weight percentage of t ert-butylalcohol in the mixed solvent, which is 10% during all measure ment. The standard electrode potential of Ag-AgCl in the mixed solvent have been determined from cell (A). The activity coefficients of HCl, gamma(A) in the mixed solvent system have been determined from cell ( B). The results show that the activity coefficients of HCl in HCl-NaCl solutions still obeys Harned Rule, The standard transfer Gibbs free e nergies of HCl have been calculated. The primary, secondary and total medium effect of HCl have been calculated and discussed.