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 (Delta G'(eta)), enthalpy of activation (Delta H-eta(not equal)), and entropy of activation (Delta S-eta(not equal)) 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. (C) 2011 Elsevier Ltd. All rights reserved.