Thermodynamics of the interaction of RbCl with some monosaccharides (d-glucose, d-galactose, d-xylose, and d-arabinose) in aqueous solutions at 298.15K

Abstract: The Gibbs energy interaction parameters of RbCl with some monosaccharides (d-glucose, d-galactose, d-xylose, and d-arabinose) in water, g ES, were obtained from electromotive force (emf) measurements of the electrochemical cell without liquid junction and containing two ion-selective electrodes (ISE): K-ISE∣RbCl(m E)∣ISE-Cl and K-ISE∣RbCl(m E),saccharide (m S)∣ISE-Cl, at 298.15K. The enthalpy interaction parameters of RbCl with these monosaccharides in water, h ES, are determined according to the McMillan–Mayer theory from the measurements of the enthalpies of mixing of aqueous RbCl solutions with aqueous monosaccharide solutions, as well as the enthalpies of dilution of RbCl and monosaccharide solutions in pure water at 298.15K by a calorimetric method. Furthermore, the entropy interaction parameters, sES, can be evaluated through g ES and h ES. The results suggest that the electrostatic interactions of these monosaccharides with RbCl in water are predominant compared with structural interactions, and these parameters are controlled primarily by the stereochemical structure of the monosaccharides in water. [Copyright &y& Elsevier]