Transport Properties of Sodium Nitrate (NaNO3) and Ammonium Nitrate (NH4NO3) in Aqueous Binary Mixture of 2-Butoxyethanol Using Electrical Conductivity

The transport properties of sodium nitrate (NaNO3) and ammonium nitrate (NH4NO3) in aqueous 2-butoxyethanol (mass fractions: 0.20, 0.40, and 0.60) mixtures were examined using electrical conductivity measurements at 298.15, 303.15, 308.15, and 313.15 K. The experimental conductance data were analyzed using the Fuoss conductance–concentration equation (1978) to evaluate ion association parameters and to gain insights into the ion–solvent and ion–ion interactions within the mixed solvent systems. The estimates of the individual ionic contributions to the limiting molar conductance were also made in this analysis. The calculated values of ion association parameters suggest a weak electrostatic ion solvent interaction for these two salts in aqueous 2-butoxyethanol mixture. Moreover, the electrolytes were found to exist predominantly as free ions across all solvent compositions and within the entire temperature range investigated in this study. The influence of temperature and solvent composition on the association constants and single-ion conductivities of the electrolytes was systematically examined and discussed. The Walden products of the ions exhibited significant deviations with changes in temperature and solvent composition.