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Densities and viscosities of the pseudo binary system 7-hydroxy-4-methylcoumarin + (ethanol or 1-propanol) + water at temperatures of (293.15, 298.15, 303.15, 308.15, and 313.15) K and refractive indices of this system at T = 298.15 K have been measured as a function of the molality of 7-hydroxy-4-methylcoumarin. The density data have been used to compute the apparent molar volume and limiting partial molar volume. The viscosity B-coefficients and variation of B with temperature have been calculated from the viscosity data according to the Jones–Dole equation. Molar refractions of the investigated system have been obtained from the refractive index data. These parameters and their variation tendencies have been expounded in terms of the interactions between solutes and solvents. The results have shown that 7-hydroxy-4-methylcoumarin plays a structure-making role in the given solution.

The enthalpies of dilution (Δ dil H m ), apparent molar volumes (V ϕ ), and refractive indices (n D ) of N,N′-hexamethylenebisacetamide (HMBA) in aqueous solutions of xylitol and D-mannitol were respectively determined at 298.15 K with the methods of isothermal microcalorimetry, density, and refractive-index measurements. The enthalpic interaction coefficients (h 2 , h 3 , and h 4 ), limiting partial molar volumes (V ϕ 0 ), and transfer partial molar volumes (Δ trs V ϕ 0 ) from water to solutions and molar refractions at the sodium-D line (R D ) were deduced from the experimental data in the polyols molality range (0 to 0.9) mol•kg −1 . The important parameters were interpreted to understand the interactions among solvated solute molecules in HMBA−xylitol (or mannitol)−water ternary systems. The results indicated that the number of hydroxyls in the both polyols could evidently affect the parameters.

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