Physico-chemical properties of some electrolytes in water and aqueous sodiumdodecyl sulfate solutions at different temperatures

The viscosities of some mineral salt viz.; potassium chloride, potassium nitrate, magnesium chloride, magnesium nitrate, at different concentrations have been determined in water and in binary aqueous solution of sodiumdodecyl sulfate (SDS) (0.007 mol · kg−1 and 0.01 mol · kg−1) at different temperatures. The data have been analyzed using Jones–Dole equation and the derivative parameters B and A   have been interpreted in terms of ion–solvent and ion–ion interactions respectively. The change of Gibbs free energy of activation (ΔGη≠), enthalpy of activation (ΔHη≠), and entropy of activation (ΔSη≠) for viscous flow of the solutions were calculated using Eyring equation, which depicts the mechanism of viscous flow. The structure making/breaking nature of the studied electrolytes has been discussed in the light of first derivative of B-coefficient (dB/dT) over temperatures. Potassium chloride and potassium nitrate acts as structure breaker in water where as all the salts are structure makers in aqueous SDS solutions, i.e. the postmicellar and pre-micellar regions.

► In this study we are trying to investigate the interaction of some mineral salts in water and aqueous SDS solutions. ► The data have been analyzed using Jones–Dole equation. ► The structure making/breaking nature of the studied electrolytes has been discussed in the light of dB/dT. ► All the studied salts are structure maker in aqueous SDS solutions.