Volumetric and ultrasonic studies of solute–solute and solute–solvent interactions of N-acetyl glycine in aqueous sucrose solutions at different temperatures

• Densities and speeds of sound of AcGly in aqueous sucrose solutions.
• Partial molar volumes and compressibility of transfer.
• Hydrophilic–hydrophilic interactions are present.
• Pair-wise and triplet interaction coefficients.

Densities (ρ) and ultrasonic speeds (u) of N-acetyl glycine in aqueous sucrose (0.05, 0.15, 0.25 and 0.35 mol kg−1) solutions have been measured as a function of molal concentration of N-acetyl glycine at temperatures (288.15, 293.15, 298.15, 303.15 and 308.15 K). Using the ρ and u   data, the partial molar volumes (Vϕ0), transfer volumes (ΔVϕ0), isentropic compression (βs), partial molar isentropic compression (Kϕ,S0), and transfer isentropic compression (ΔKϕ,S0) have been computed. Transfer parameters have been discussed in terms of solute-co-solute interactions on the basis of co-sphere overlap model. Partial molar expansibilities (Eϕ0) and interaction coefficients have also been calculated from these data. The results have been interpreted in terms of solute–solute and solute–solvent interactions in these systems. It is observed that there exist strong solute–solvent interactions in these systems, which increase with increase in temperature.