With using new data of osmotic coefficients and activity coefficients within more wider range of concentration

the energy parameters of single salts involved in the system Na+

K+

Mg2+/Cl~-

SO42-

NO3~--H_2O have been evaluated again by utilizing the optimizing method of MatLab.The mean square deviations for valuating parameters using the data of osmotic coefficients are smaller than using the data of activity coefficients or activity coefficients + osmotic coefficients.The mean square deviations for valuating parameters of potassium salt

sodium salt are small

but great for Magnesium salt.The mean square deviations for valuating parameters relevant to the sorts of ions

the effect of anions on the mean square deviations for valuating parameters are greater than cations.