Calorimetric and isentropic compressibility studies on (saccharide/methyl glycoside/deoxy-derivative + KH2PO4 + H2O) solutions at different temperatures

Heats of dilution (q) of various saccharides and their methyl-/deoxy-derivatives (solutes) have been measured in water and in (0.05, 0.15, 025 and 0.35) mol kg(-1) aqueous potassium phosphate monobasic (KH2PO4) solutions at (288.15, 298.15, 308.15, and 318.15) K. Limiting standard enthalpies of dilution (Delta H-dil degrees) for the solutes were calculated from data q measured using isothermal titration micro calorimeter. The speed of sound (u) of solutes was measured in water and in (0.25, 0.50, 1.00 and 1.25) mol kg(-1) KH2PO4 solutions at (288.15-318.15) K. From these data, the apparent molar isentropic compressibilities (K-s,K-2,K-Phi), interaction coefficients, hydration numbers and transfer parameters (Delta(t)Delta H-dil degrees, Delta K-t degrees(s,2)) have been calculated. These parameters have been discussed in terms of solute-solvent/cosolute interactions occurring in these solutions. The results suggest that saccharides and their derivatives act as kosmotropes in mixed aqueous solvent. (C) 2016 Elsevier B.V. All rights reserved.