Activity coefficients for the system NaCl+Na 2 SO 4 +H 2 O at various temperatures. Application of Pitzer's equations

The mean activity coefficients of NaCl in the system NaCl+Na2SO4+H2O at various compositions were determined in the temperature range 5–45°C from the emf of potentiometric cells. By processing the results using Pitzer's equations the mixing parameters describing the non-ideal behavior of electrolytes were calculated. The temperature coefficients of the mixing parameters were determined and found not to be significant. The mixing parameters and temperature coefficients calculated for the binary mixture can be used to describe the behavior of multicomponent systems containing NaCl and Na2SO4, and eventually sea water.