Isothermal compressibility and internal pressure studies of some non-electrolytes in aqueous solutions at low temperatures

摘要: Abstract The experimental data of density (ρ) and sound velocity (u) in the temperature range (275.15 to 293.15) K have been obtained for systems (dioxane + water), (dimethylformamide + water), (tetrahydrofuran + water), (acetonitrile + water). specific heat (Cp) above at T = 279.15 K. are used calculate derived parameters adiabatic compressibility (βS), T = 275.15 K T = 283.15 K, isothermal (βT), internal pressure (Pi) T = 279.15 K different concentrations. solute properties: apparent molar volume (ϕV), expansivity (ϕE), (ϕKS) studied limiting values these properties reported. variation with concentration corresponding effects discussed terms hydrophobic hydration (–H bonding interaction) interaction (non-polar group solute–solute association water). It is noted that solutions quite insensitive region association, while its dilute sensitive contrast aqueous alcohol solutions. molecular interactions also exhibit individualistic behaviour much dependent on structural alterations water structure.