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In the present work, density, ρ and speed of sound, u measurements have been performed, for binary mixtures of two synthesized Bronsted-acidic ionic liquids namely N,N,N-triethyl-4-sulfobutaneammonium hydrogensulfate, [N222(C4SO3H)][HSO4] and N,N,N-triethyl-4-sulfobutaneammonium trifluoromethanesulfonate, [N222(C4SO3H)][CF3SO3] with water and DMSO as solvents. Experimental measurements have been carried out at variable concentrations of ILs in the temperature range of (293.15 to 328.15) K with the constant interval of 5 K and at atmospheric pressure. Using experimentally measured density and speed of sound data, apparent molar volume, Vϕ and apparent molar isentropic compressibility, Ks, ϕ and limiting apparent molar expansion, Eϕ∞ have additionally been derived for the studied binary solutions. Apparent molar property data were fitted to the Redlich-Mayer type equation from which corresponding derived properties i.e. apparent molar volume and apparent molar isentropic compressibility at infinite dilutions, Vϕ∞ and κs, ϕ∞ were attained. Magnitude of these derived properties and corresponding empirical parameters were evaluated in the scope of understanding the nature of interactions prevailing among ions of ILs as well as ions and solvents.

Densities and refractive indices of three naphthyl hydroxamic acids, N -1-naphthyl- o -ethoxybenzohydroxamic acid (NEBHA), N -1-naphthyl- o -methylbenzohydroxamic acid ( N - o -MBHA) and N -1-naphthyl- p -methylbenzohydroxamic acid ( N - p -MBHA) were determined in ethanol under atmospheric pressure at T = (298.15 to 313.15 K). This study was undertaken to determine molar volume, V , specific molar volume, V S , apparent molar volume, V ϕ , apparent molar volume at infinite dilution, V ϕ 0 , and slope, S V ⁎ , based on the Masson's equation. The apparent molar expansibility at infinite dilution, ϕ E 0 , thermal expansion coefficient, α 2 , and Hepler's constant, ( ∂ 2 V ϕ 0 / ∂ T 2 ) P , have also been calculated from temperature dependence of V ϕ 0 . The steric parameters such as molar refraction, R M , and polarizability, α , have been determined from the refractive index, n , data. Excess molar volume, V E , excess refractive index, n E , excess molar refraction, R M E , and vander Waal constant, b , have also been estimated. These parameters have been used to understand the solute–solute and solute–solvent interactions qualitatively.

In continuation of our previous works, using the density measurement, we studied some important volumetric properties such as: apparent molar volumes, standard partial molar volumes, limiting apparent molar volumes of transfer, and limiting apparent molar expansibility for the ternary (ionic liquids 1-Ethyl-3-methylimidazolium hydrogen sulfate [Emim][HSO4] / 1-Butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF4] + D(−)fructose + water) at T = (293.15 to 313.15) K. By using the standard partial molar volumes and limiting apparent molar volumes of transfer, the nature of possible interactions in studied solutions are considered. Results demonstrated that for both studied ionic liquids, the Vφ values are increased with rising concentration of ionic liquids and temperature. Also by applying the first derivative of limiting apparent molar expansibility with respect to temperature, the structure maker ability of studied ionic liquids in aqueous D(−)fructose solutions are confirmed.

Drug interactions in presence of co-solute in aqueous solution have always created an interest in the mind of chemists. The physical properties give an idea of types of interactions taking place in aqueous solution. Volumetric and compressibility are the important physical properties. Keeping this in mind we have measured the densities ( ρ ) and speeds of sound ( u ) of sodium salicylate (NaSl) drug (0.01–0.1) mol·kg−1 in 0.06 mol·kg−1 aqueous sodium chloride solution and 0.06 mol·kg−1 myo-inositol as a function of temperature at T = (288.15, 298.15 and 308.15) K and atmospheric pressure. These values have been used to estimate the apparent molar volume of solute ( V ϕ ) , apparent molar isentropic compressibility ( κ s ) of solution and apparent molar isentropic compressibility ( κ ϕ ) of solute. The limiting apparent molar expansivity ( E ϕ 0 ) of solute and coefficient of thermal expansion ( α ∗ ) of sodium salicylate in aqueous binary and ternary solutions have also been obtained. Limiting values of apparent molar volume of solute ( V ϕ 0 ) and apparent molar compressibility of solute ( κ ϕ 0 ) were obtained from the plots V ϕ and κ ϕ as a function of molality and have been utilized in obtaining transfer volumes ( Δ tr V ϕ 0 ) and transfer compressibilities ( Δ tr κ ϕ 0 ) of sodium salicylate from water to 0.06 mol·kg−1 aqueous solutions of sodium chloride and myo-inositol at different temperatures. The co-sphere overlap model is used to interpret the values of ( Δ tr V ϕ 0 ) and ( Δ tr κ ϕ 0 ) . The Helper’s constant has been obtained. It indicates structure making ability of sodium salicylate in aqueous as well as in 0.06 mol·kg−1 aqueous sodium chloride and 0.06 mol·kg−1 aqueous myo-inositol solutions. The results obtained have been interpreted in terms of various interactions taking place among solute and solvent molecules.

Densities, ultrasonic speeds and viscosities of l -alanine and l -phenylalanine in water and in 0.1 mol·kg− 1 aqueous citric acid solutions were measured over the temperature range (298.15 to 313.15) K with interval of 5 K at atmospheric pressure. From these experimental data apparent molar volume, limiting apparent molar volume and the slope, partial molar expansibilities, adiabatic compressibility, transfer volume, Falkenhagen coefficient, Jone-Dole's coefficient, the temperature derivative of Jone-Dole's coefficient, intermolecular free length, specific acoustic impedance, and molar compressibility were calculated. The results are interpreted in terms of solute – solute and solute-solvent interactions in these systems. It has also been observed that l -alanine acts as a structure breaker whereas l -phenylalanine acts as a structure maker in aqueous citric acid.

Density, sound velocity and viscosity of DL-4-aminobutyric acid (GABA) in water and in aqueous sodium chloride solutions have been measured at (293.15, 298.15, 303.15, 308.15 and 313.15) K. The apparent molar volumes and the apparent molar compressibilities were calculated at each temperature from the experimental density and sound velocity data. Limiting values at infinite dilution of the partial molar volumes and the partial molar compressibilities of GABA in water and in aqueous sodium chloride solutions were determined through extrapolation at each temperature. The relative viscosity data were adjusted by a least-squares method to a second order equation as proposed by Tsangaris-Martin to obtain the viscosity B coefficients. The influence of temperature on the behaviour of viscosity and the volumetric properties is discussed in terms of molecular interactions. The results confirm that hydrophilic hydration is predominant for GABA in aqueous solution. The addition of NaCl leads to an increase of the partial molar properties at infinite dilution and the viscosity B-coefficients, suggesting that the sodium and the chloride ions interact directly with the zwitterion, reducing the electrostriction of water molecules.

Deep eutectic solvents (DESs) are derived from two or more salts as the hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs). In this work, DES namely allyltriphenyl phosphonium bromide-diethylene glycol (ATPPB-DEG) was prepared by using three molar ratios of 1:4, 1:10 and 1:16 salt to HBD. The volumetric properties of aqueous DESs, such as density, molar volume, isobaric thermal expansion, apparent molar volume and apparent molar expansibility were reported at several temperatures from 293.15 to 343.15 K. A mathematical equation, so-called Jouyban–Acree model (JAM), was used to correlate the experimental density and molar volume data of aqueous solution of DESs with respect to the concentration and temperature. The results disclosed that this model is an accurate and reliable model for the prediction of aqueous DES properties. The excess properties, such as excess molar volume and excess isobaric thermal expansion were reported and fitted to two different equations. In order to calculate the limiting apparent molar volume values, the apparent molar volume values were fitted into a Redlich–Mayer equation. By applying the Hepler equation, it was found that DESs with molar ratios of 1:4 and 1:10 are as structure-maker solutes, while the DES 1:16 is a structure-breaking solute in aqueous solutions at different temperatures.

The apparent molar volume ( V ∅ ) and isentropic compression ( K ∅ s ) of glycine, L-alanine and L-valine have been studied in (0.025, 0.05, 0.075 and 0.1) mol·kg−1 aqueous 1-butyl-4-methyl pyridinium iodide [ C 4 mpy ] I solutions over a range of temperatures (288.15, 293.15, 298.15, 303.15 and 308.15) K from the values of densities (ρ) and ultrasonic speeds (u) respectively. The limiting apparent molar volumes ( V ∅ 0 ) , and limiting apparent molar isentropic compressions ( K ∅ ,s 0 ) are obtained and have been interpreted in terms of solute-solvent and solute-solute interactions. The corresponding transfer quantities ( Δ V ∅ 0 and Δ K ∅ ,s 0 ) from water to aqueous solutions of [ C 4 mpy ] I have been interpreted by cosphere overlap model. Volumetric and acoustic parameters are used to understand mixing effects and other complex biological processes between head and side chain groups of amino acids and ionic liquid in aqueous solution. The decrease in hydration number with increase in temperature indicates the reduction in electrostriction.

Deep eutectic solvents (DESs) are derived from two or more salts as the hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs). In this work, DES namely allyltriphenylphosphonium bromide- triethylene glycol (ATPPB-TEG) was prepared by using three molar ratios; i.e.,1:4, 1:10, and 1:16 of salt to HBDs. The volumetric properties of aqueous mixture of DESs, such as density, molar volume, isobaric thermal expansion, apparent molar volume and apparent molar expansibility were reported at several temperatures from 293.15 to 343.15 K. A mathematical equation, namely Jouyban–Acree model (JAM), was used to correlate the experimental density and molar volume data. Furthermore, in order to calculate the limiting apparent molar volume values, the apparent molar volume values were fitted into a Redlich–Mayer equation. By applying Hepler equation, it was found that DESs 1:4 and 1:10 are as structure-maker solutes, while DES 1:16 is a structure-breaking solute in aqueous solutions.

Densities (ρ) and speeds of sound (c) measurements of d (−)-ribose and d (+)-xylose in (0.2, 0.4, 0.6) mol·kg−1 aqueous solutions of trilithium citrate (TLC) have been carried out at different temperatures. The experimental results were used to calculate apparent molar and partial molar quantities, partial molar volumes and partial molar isentropic compression of transfer. The pair and triplet interaction coefficients are computed from transfer parameters. The partial molar expansibilities have also been calculated. The results have been interpreted in terms of prevailing interactions and structure making and breaking tendency of the solutes in aqueous solution of TLC.

In order to analyze the extent of solvation behaviour and stability of ascorbic acid (AA) in water or aqueous ionic liquid (IL) solutions, the knowledge of their thermodynamic properties is prerequisite which gives an appropriate idea about interactions involved in solutions. In addition, experimental and derived thermodynamic data is essential in effective process and product design involving these systems. In this report, we studied the volumetric and acoustic properties of AA in aqueous solution of synthesized IL, [HxTzm][CF 3 SO 3 ] i.e. (1-Hexyl-4-(4-sulfobutyl)-1H-1,2,4-triazol-4-ium trifluoromethanesulfonate) in temperature range of (293.15–328.15) K and at atmospheric pressure. Further, the experimentally measured thermodynamic properties were used to calculate apparent molar and partial molar properties, which elucidate the solvation behaviour of AA in presence of studied IL. Further, on the basis of the structural interaction model, various type of interactions which is stirring between AA and IL have been discussed in terms of partial molar properties at infinite dilution, transfer parameters and pair and triplet interaction coefficients.

In this investigation density, speed of sound and viscosity of l -histidine (0.015–0.135) mol kg− 1 in aqueous ketorolac tromethamine solutions (0.1–0.7) mol kg− 1 at various temperatures (293.15, 298.15, 303.15, 308.15 and 308.15) K and at atmospheric pressure were studied. These data were further used to calculate apparent molar volume, VΦ, limiting apparent molar volume, V°Φ, limiting apparent molar volume of transfer, V°Φ,tr, apparent molar isentropic compression, KΦ,S, limiting molar isentropic compression, K°Φ,S, limiting apparent molar isentropic compression of transfer, K°Φ,S,tr, hydration number, nH, Jones-Dole coefficient-B, B, viscosity B-coefficients of transfer, Btr and the activation parameters, ∆ μ°#1 and ∆ μ°#2. The results obtained from all these thermodynamic parameters were discussed in terms of solute-solute interactions and solute-solvent interactions on the basis of co-sphere overlap model and the transition state theory.

The volumetric and compressibility properties of l -serine and l -valine in the concentration range (0.0 to 0.2) mol kg− 1 in water and various saccharides (0.1 glucose, 0.1 sucrose and 0.1 lactose) mol dm− 3 have been studied over a temperature range of (293.15 to 313.15) K. The experimental data is used to obtain the apparent molar volume (Vϕ), limiting apparent molar volume (Voϕ), limiting apparent molar transfer volume (∆trVoϕ), as well as apparent molar compressibility (Ks,ϕ), limiting apparent molar compressibility (Kos,ϕ), limiting apparent molar transfer compressibility (∆trKos,ϕ), limiting partial molar expansibility (ϕoE), coefficient of thermal expansion (α), hydration number (nH) and taste behavior of amino acids. The results have been interpreted in terms of solute-solute and solute-solvent interactions. As the taste behavior is divided into four basic taste qualities in different ranges, so an effort has also been made to compare the taste behavior of the two amino acids in water and in aqueous solution of saccharides.

Ionic liquid 1-methyl-3-pentylimidazolium bromide have been synthesised and its extent of purity has been confirmed by characterisation techniques 1H NMR, 13C NMR, MASS and IR spectroscopy. By use of volumetric and acoustic methods the interaction of amino acids ( l -leucine and N-acetyl- l -leucine) and synthesised Ionic liquid 1-methyl-3-pentylimidazolium bromide have been studied as a function of temperature and concentration. Density and speed of sound of aqueous amino acids ( l -leucine and N-acetyl- l -leucine) in aqueous ionic liquid (0.005, 0.01, 0.03, 0.05) mol·kg− 1 as solvent have been determined at four different temperatures T = (288.15, 298.15, 308.15, 318.15) K. Using these experimental data apparent molar volumes (Vϕ), limiting apparent molar volume (Vϕ0), experimental slope (SV), standard partial molar volumes of transfer (ΔVϕ0), limiting apparent molar expansibilities (Eϕ°),apparent molar isentropic compression (κϕ , s), limiting apparent molar isentropic compression (κϕ , s0)and standard partial molar isentropic compression of transfer (Δκϕ , s0)have been evaluated. The pair and triplet interaction coefficient have also been calculated. The values of these parameters are used for interpretation in terms of solute-solute and solute-solvent interactions, ion hydrophilic, hydrophilic–hydrophilic and hydrophilic– hydrophobic interactions in the amino acid and ionic liquid solutions. The structure making or structure-breaking tendency of amino acids has been studied using these thermodynamic parameters.

Thermodynamic properties of l -threonine and l -valine in aqueous solution of 1-methyl-3-pentylimidazolium chloride, [C5mim][Cl] have been investigated by volumetric and ultrasonic properties at three different temperatures (T = (288.15, 298.15 and 308.15) K). Other properties at infinite dilution like apparent molar volume, Vϕ0 and the apparent molar isentropic compression Kϕ , S0, have also been calculated from the measured data. Conclusion drawn from volumetric and ultrasonic properties have been further supported by calculating apparent molar expansion, Eϕ0, Hepler's constant values, ∂ E ϕ 0 ∂ T P , hydration numbers, nH and specific volume, vϕ. The calculated parameters are worthwhile in studying structure nurturing, solvation as well as taste behavior on the basis of various kinds of interactions present in such solutions.

Densities and viscosities of glycine, L-alanine, L-valine, L-threonine and L-arginine in aqueous (0.1–0.5) mol·kg− 1 myo-inositol solutions were measured at T = (293.15, 303.15, 313.15 and 323.15) K and p = 0.101 MPa. The volumetric properties such as the apparent molar volume (Vφ), the limiting partial molar volume (Vφ0), the limiting partial molar volumes of transfer (ΔtrVφ0), the limiting apparent molar expansibility (E20), Hepler's constant and the isobaric thermal expansion coefficient (α2) were calculated through density. The viscometric properties such as the B-coefficient, the free energies of activation per mole of solvent (Δμ10 ≠) and solute (Δμ20 ≠) were obtained from the experimental viscosity data. The derived parameters hydration number and solvation number were also calculated through apparent molar volume and B-coefficient. From the volumetric and viscometric properties, the solute-solute and solute-solvent interactions in the studied systems were analyzed on the basis of co-sphere overlap model and transition state theory. Finally, the group contribution method was applied to calculate the contribution of (NH3+, COO−), CH2, OH and CNHNHNH2 of amino acids to Vφ0, B-coefficient and Δμ20 ≠.

The solvation behavior of ionic liquids containing a common, 1,1,3,3-tetramethylguanidinium cation and different anions, phenylacetate and cinnamate, in water is examined through apparent molar properties. These ionic liquids were chosen because of their versatile applications as environment-friendly solvent, catalyst, and for dissolution and stability of biomolecules. In order to understand the ion-ion and ion-solvent interactions and effect of anion in dilute aqueous solutions of studied ionic liquids, the experimental measurements of density and speed of sound have been carried out as a function of molality (0.01 to 0.2 mol·kg − 1 ) and temperature from 293.15 to 318.15 K. Experimental data have been used to calculate the apparent molar and other derived thermodynamic properties. Further, Redlich-Meyer equation has been employed to obtain the apparent molar volume and isentropic compressibility at infinite dilution and the empirical parameters which are crucial in understating the hydrophilic and hydrophobic nature of studied ionic liquids.

Densities, ρ, ultrasonic speeds, u and viscosities, ƞ of glycine and diglycine in water and 0.1 mol·kg− 1 aqueous citric acid solutions were measured over the temperature range (298.15 to 313.15) K at the interval of 5 K at atmospheric pressure. From these experimental data apparent molar volume ФV, limiting apparent molar volume ФVO and the slope SV, partial molar expansibilities ФEO, adiabatic compressibility β, transfer volume ФVOtr, Falkenhagen coefficient A, Jone- Dole coefficient B, the temperature derivative of B coefficient dB/dT, intermolecular free length (Lf), specific acoustic impedance (Z), and molar compressibility (W) were calculated. The results are interpreted in terms of solute–solute and solute-solvent interactions. It was observed that glycine and diglycine act as structure breakers in aqueous citric acid at different temperatures.

The density and speed of sound measurements have been carried out for some α-amino acids i.e. glycine, l -alanine and l -valine in aqueous diammonium hydrogen phosphate (DAP) at 10 K intervals, from 288.15 K to 318.15 K and experimental pressure p = 0.1 MPa. We have utilized the density and speed of sound data for determining the apparent molar and partial molar parameters concerning volumetric and compressibility properties. The group contribution of amino acids to partial molar volumes has also been perceived. The pair and triplet interaction coefficients obtained from partial molar volumes of transfer and partial molar isentropic compression of transfer illustrate the dominance of pairwise interactions. The possible molecular associations such as solute-solvent and solute-solute etc. are revealed by the present work and in due course, it has also been observed that all the amino acids in our present study, act as structure makers in aqueous solution of diammonium hydrogen phosphate (DAP). Apparent molar properties and partial molar properties anticipate the dominance of strong solute–solvent interactions over weak solute-solute in the studied ternary system.

Apparent molar volumes, V ϕ , and apparent molar heat capacities, C p,ϕ , were measured for aqueous solutions of neutral adenine (AdH) and adeninium chloride (AdH 2 Cl) at temperatures from 288.15 K to 363.15 K, and for sodium adeninate (NaAd) at temperatures from 283.15 K to 313.15 K. Density measurements used in the determination of the standard partial molar volume, V o , were made with a vibrating-tube densimeter at ambient pressure. Heat capacity measurements used in the determination of the standard partial molar heat capacity, C p o , were made with a twin fixed-cell, differential output, power compensating, temperature-scanning calorimeter at a pressure of 0.4 MPa. The contributions from minor equilibrium species were removed using Young’s Rule to yield values for the standard partial molar volume and heat capacities of the ionic species AdH 2 + (aq) and Ad − (aq), and the equilibrium mixture of neutral species AdH ∗ (aq). Semi-empirical equations describing the temperature dependence of V o and C p o for each species were fitted by regression to the experimental results. From these equations, the standard partial molar volume change Δ r V o m and heat capacity change Δ r C p o m for the ionization reactions were calculated. The standard partial molar volumes presented in this study for neutral adenine are the first to be experimentally determined at temperatures above 330 K, while the standard partial molar heat capacities are the first to be reported at temperatures above 298.15 K. The experimental values for the adeninium cation and adeninate anion are the first to be reported in the literature.

Apparent molar volume, Vϕ, apparent molar isentropic compression, K ϕ,s and viscosity B-coefficients have been evaluated for one of the vitamins, thiamine hydrochloride (thiamine-HCl), in aqueous solutions of two carbohydrates, glucose and lactose, at temperatures (293.15–313.15) K from density, speed of sound and viscosity data. Accordingly, limiting apparent molar volume, V 0ϕ, was obtained from Redlich-Meyer equation whereas limiting apparent molar isentropic compression, K 0ϕ,s, was calculated on the basis of Debye-Huckel theory. The transfer parameters (ΔtrV 0ϕ, ΔtrK 0ϕ,s and ΔtrB) at infinite dilution, limiting apparent molar expansivity, E 0ϕ, Hepler's constant, (∂2V 0ϕ/∂ T2)P, thermal expansion coefficient, α, pair and triplet interaction coefficients and solvation number, Sn, have also been estimated. The viscosity B-coefficients and activation parameters have been obtained from Jones-Dole equation and transition state theory. The results have been discussed in terms of competing patterns of interactions prevailing in the solute and solvent.

Ionic liquid 1-methyl-3-pentylimidazolium bromide have been synthesised and confirmed by characterisation techniques H 1 NMR, C 13 NMR, MASS and IR spectroscopy. Density and speed of sound of aqueous amino acids (L-cysteine and N-acetyl- l -cysteine) in aqueous ionic liquid (0.005, 0.01, 0.03, 0.05) mol⋅kg −1 as solvent have been determined at four different temperatures T = (288.15, 298.15, 308.15, 318.15) K. Using these experimental data apparent molar volumes ( V ϕ ), limiting apparent molar volume ( V ϕ ° ), experimental slope ( S v ), standard partial molar volumes of transfer (Δ V ϕ 0 ), Limiting apparent molar expansibilities ( E ϕ ∘ ), apparent molar isentropic compression ( К ϕ,s ), limiting apparent molar isentropic compression ( κ ϕ , s 0 ) and standard partial molar isentropic compression of transfer (Δ κ ϕ , s 0 ) have been evaluated. The pair and triplet interaction coefficient have also been calculated. The values of these parameters are helpful for interpretation in terms of solute-solute and solute-solvent interactions, ion hydrophilic, hydrophilic–hydrophilic and hydrophilic–hydrophobic interactions in the amino acid and ionic liquid solutions. The structure making or structure-breaking tendency of amino acids has also been studied using these thermodynamic parameters.

Density and sound velocity data for aspartic acid and serine in water and in aqueous solution of anionic surfactant; Sodium dodecyl sulphate (SDS) were measured over a temperature range (303.15 K–313.15 K). Various volumetric and acoustical parameters including apparent molar volume (Φv), partial molar volume (Φvo), partial molar transfer volume, apparent molar isentropic compressibility (Φk), partial molar isentropic compressibility (Φok) and intermolecular free length (Lf) etc. for amino acid solutions in water and in aqueous surfactant (SDS) solutions were calculated from the measured data of density and sound velocity. The abovementioned calculated parameters have been used to explore the amino acid-surfactant interactions. Values of apparent molar volume are positive at all temperatures and are increasing with increasing temperature and amino acids concentrations. Similarly, intermolecular free length decreases with increasing amino acids concentrations both in water and aqueous surfactants solutions, which indicate strong intermolecular interactions in amino acids solutions. From results it is also obvious that due to the presence of resonance stabilization, aspartic acid interacts more strongly in both aqueous and SDS environment than serine.

The density, d, viscosity, η, and the conductance, Λ, values of solutions of l -phenylalanine in aqueous and aqueous solutions of d -glucose (5, 10, 15, and 20 wt%) have been determined at four different temperatures ranging from 298.15 K to 313.15 K at 5 K intervals. Sound velocity has been measured at 298.15 K. The experimental data were used to calculate apparent molar volume, Vφ, limiting apparent molar volume, Vφ°, apparent molar isentropic compressibility, Ks,φ, and limiting apparent molar isentropic compressibility, Ks,φ°. The derived acoustical and thermodynamics parameters, namely isentropic compressibility, Ks, specific acoustic impedance, Z, molar compressibility, W, molar sound velocity, R, free length, Lf, and relative association, RA, have been calculated. Shedlovsky equation has been used to obtain limiting molar conductance, Λm°, from the conductance data. The results have been discussed in terms of solute–solute, solute–solvent and solvent–solvent interactions.

The density, dynamic viscosity, and dielectric constant of propylene carbonate solutions with acetonitrile are measured over the composition of a mixed solvent at temperatures of 253.15, 273.15, 293.15, and 313.15 K. The molar volume, molar viscosity, and molar capacity of a mixture of propylene carbonate–acetonitrile and an excess amount of it are calculated. The effect the temperature and composition of the mixture have on the excess molar properties is discussed. A linear correlation is observed between the values of the molar fluidity, capacity, polarization, and molar volume of the studied system.

In this work, experimental densities (ρ), speeds of sound (u) and relative viscosities (ηr) of DIL i.e. 1, 1-(propane-1, 3-diyl)-bis (3-methyl-1H-imidazolium-1-yl) dibromide or Bis C3 (mim) Br2 in aqueous solution 0.1 mol kg− 1 of d -glucose as a function of concentration have been measured at T/K = (293.15, 298.15, 303.15, 308.15 and 313.15). From these experimental data, thermodynamic and transport functions such as apparent molar volume (Vϕ) of solute, limiting apparent molar volume of solute (Vϕ0), isentropic compressibility(κs), apparent molar isentropic compressibility (κϕ) of solute, limiting apparent molar compressibility of solute (κϕ0), limiting apparent molar expansivity (Eϕ0) of solute, thermal expansion coefficient(α∗), Jones-Dole viscosity coefficientsA, Β, D variation of viscosity Βcoefficient with temperature i.e. dΒ/dT, hydration number of DIL in water and in aqueous solutions of d -glucose have been calculated. Transfer volumes Δ tr V ϕ 0 and transfer compressibilities Δ tr κ ϕ 0 of DIL from water to aqueous solutions of d -glucose at different temperatures have also been obtained. The results obtained have been interpreted in terms of various interactions taking place among solute and solvent molecules.

Volumetric and ultrasonic properties of ionic liquid (IL) with molecular solvents are important parameter for elucidation of solute-solute and solute-solvent interactions occurring in solutions. In the present work, the density, ρ and speed of sound, u for binary solutions of the protic ionic liquid (1,8-diazabicyclo [5.4.0] undec-7-en-8-ium trifluromethane sulfonate), with molecular solvents like water and ethanol have been measured as a function of molality in temperature range (293.15 to 318.15) K and at atmospheric pressure. From the experimental data, apparent molar volume, V φ , apparent molar isentropic compression, K s ,φ and limiting apparent molar expansion, E φ ∞ have been calculated. Further, to understand the extent of interaction between studied IL and solvents the apparent molar properties at infinite dilution were analyzed by using Redlich-Mayer type equation.

The solute–solvent interactions in the studied aqueous ternary systems containing some amino acids (Glycine or l -serine) and ionic liquid (1-butyl-3-methylimidazolium tetra fluoroborate [Bmim][BF4]) are studied by using the volumetric properties data. These properties contains: apparent molar volumes, standard partial molar volumes, limiting partial molar volumes of transfer, apparent molar expansibility and hydration number. Vφ values were increased when rising concentration of amino acids and also temperature while decreased by increasing concentration of ionic liquid. Apparent molar volumes of transfer, ΔVφ0, for studied amino acids from water to aqueous solutions of ionic liquid (IL) are calculated. The limiting partial molar volumes of transfer ΔtVφ0 values were negative. Results confirmed the dominance of hydrophobic-hydrophobic interactions in both ternary solutions.

Thermodynamic properties of glycine and its dipeptide diglycine in aqueous solution of 1-pentyl-3-methylimidazolium chloride, [C5mim][Cl] have been investigated by volumetric and ultrasonic properties at T = (288.15–308.15 K). The apparent molar volumes at infinite dilution, Vϕ0 and the apparent molar isentropic compression at infinite dilution Kϕ , S0, have been calculated from density and speed of sound data. Furthermore, apparent molar expansivity, Eϕ0, Hepler's constant values, ∂ E ϕ 0 ∂ T P and hydration numbers, nH have been evaluated to support the conclusions obtained from the volumetric and acoustic studies. These parameters are helpful to study the structure nurturing, solvation behavior and various interactions present in the ternary solutions of (amino acid/dipeptide + [C5mim][Cl] + water).

Morpholine, having its applications in process industries is also used as an anticancer agent as well as a building block in the preparation of linezolid antibiotic. 1-decanol can be used as a suitable solvent for recovery of morpholine from its aqueous stream. The present study involves VLE studies and volumetric properties of the morpholine + 1-decanol, at 13.32, 39.99, 66.66 and 94.90 kPa. Wilson, NRTL, and UNIFAC models were used to correlate and predict the experimental VLE data. Further, thermodynamic properties such as excess molar volume ( V m E ), and deviation in molar refractivity (ΔR). Partial molar volume ( V ¯ i ), apparent molar volume ( V ϕ i ) and excess partial molar volume ( V ¯ i E ) were also estimated. Moreover, all the above thermodynamic properties have also been estimated for the 1-octanol + toluene mixture at different temperatures. The applicability of Prigogine–Flory–Patterson theory and different mixing rules were tested for the excess molar volumes and refractive indices, respectively.

The interactions of salt trilithium citrate (TLC) with saccharides d (+)-glucose and d (−)-fructose, have been investigated in aqueous medium from density ( ρ ) and speed of sound ( c ) measurements at T = (288.15–318.15) K and experimental pressure p = 0.1 MPa. The apparent molar volume ( V ϕ ), the partial molar volume ( V ϕ o ) and standard partial molar volumes of transfer ( Δ V ϕ o ) for both saccharides, from water to aqueous trilithium citrate (TLC) have been calculated from density data. The limiting apparent molar expansibilities have also been calculated. The apparent molar isentropic compression ( K ϕ , s ), partial molar isentropic compression ( K ϕ , s o ) and partial molar isentropic compression of transfer ( Δ K ϕ , s o ) have been calculated from speed of sound results. The pair and triplet interaction coefficients have been calculated from partial molar volumes of transfer and partial molar isentropic compression of transfer. A detailed insight into the physicochemical interactions e.g. ion–hydrophilic, hydrophilic–hydrophilic and hydrophilic–hydrophobic interactions in the saccharide-salt system along with the structure-making/structure-breaking tendency of the saccharides, have been retrieved through the perusal of these calculated parameters.

Amino acids are the building blocks of proteins and their study provides important information, which can be related to the behavior of larger biomolecules such as proteins. The present article reports experimental values of density (ρ) and speed of sound (u) of aqueous binary mixtures of biologically important amino acid derivatives, namely, l -alanine methyl ester hydrochloride and l -valine methyl ester hydrochloride at different temperatures i.e. T = (278.15, 288.15 and 298.15) K within the concentration range of (0–0.16) mol·kg−1. The obtained data of densities and speeds of sound of solutions were processed to obtain different derived parameters, such as apparent molar volume of solute (Vϕ), isentropic compressibility of solution (κs) and apparent molar isentropic compressibility of solute (κϕ). The limiting values of apparent molar volume of solute ( V ϕ 0 ) , apparent molar isentropic compressibility of solute ( κ ϕ 0 ) , apparent molar expansivity ( E ϕ 0 ) of solute, coefficient of thermal expansion ( α ∗ ) , hydration number ( n H ) and second derivative of limiting apparent molar volume ( ∂ 2 V ϕ 0 / ∂ T 2 ) have also been computed. The results have been interpreted in terms of various interactions occurring among solute and solvent molecules and structure making and structure breaking tendencies of the solute in these aqueous binary systems.

Density, sound velocity and viscosity of DL-2-aminobutyric acid in water and in aqueous sodium chloride solutions have been measured at temperatures of (293.15, 298.15, 303.15, 308.15 and 313.15) K. The experimental results were used to determine the apparent molar volume and the apparent molar compressibility as a function of composition at these temperatures. The limiting values of both the partial molar volume and the partial molar adiabatic compressibility at infinite dilution of DL-2-aminobutyric acid in water and in aqueous sodium chloride solutions were determined at each temperature. The experimental viscosity values were adjusted by a least-squares method to a second order equation as proposed by Tsangaris-Martin to obtain the viscosity B coefficient which depends on the size, shape and charge of the solute molecule. The influence of the temperature on the behaviour of the selected properties is discussed in terms of both the solute hydration and the balance between hydrophobic and hydrophilic interactions between the acids and water, and the effect of the sodium chloride concentration.

Apparent molar volumes and molar isentropic compressibilities for N -ethyl- N -methylmorpholinium and N -decyl- N -methylmorpholinium tetrafluoroborates in N , N -dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) have been determined from density and speed of sound measurements over the temperature range T = (298.15, 303.15, 308.15, 313.15, 318.15 and 328.15) K at experimental pressure p = 0.1 MPa. This data has been used to calculate partial molar volumes and partial molar isentropic compressibilities at infinite dilution. The partial molar expansion coefficients and their secondary derivative have been estimated as well. The obtained results indicate that dimethyl sulfoxide interacts more effectively with ionic liquids studied than N , N -dimetylformamide and ion–ion interaction are stronger for N , N -dimetylformamide solutions than corresponding in dimethyl sulfoxide. Moreover the temperature dependence of the limiting apparent molar volumes and compressibilities is a result of temperature influence on the electrostriction effect, the ordering of a bulk solvent and number solvent molecules in the nearest presence of the salt.

The volumetric, acoustic and viscometric approach has been used for investigating the interactions of l -serine, l -threonine and l -leucine in aqueous solutions of an antimycobacterial drug, namely, streptomycin sulfate, over a temperature range of (305.15, 310.15 and 315.15) K at atmospheric pressure. The apparent molar volume, Vϕ, limiting apparent molar volume, V 0ϕ, the slope, Sv, partial molar volume of transfer, V 0ϕ, tr, limiting apparent molar expansivity, E 0ϕ, and Hepler's constant, (∂2V 0ϕ/∂ T2)P, have been calculated from density data. The apparent molar isentropic compression, K ϕ,s, limiting apparent molar isentropic compression, K 0ϕ,s, its slope, Sk, and partial molar isentropic compression of transfer, K 0ϕ,s,tr, have been calculated from speed of sound data. The compression data is also used for calculating the number of water molecules hydrated, nH, to the amino acids. The viscosity data has been used to determine relative viscosity ηr, viscosity B-coefficients, temperature derivative of B-coefficients, dB/dT and viscosity B-coefficients of transfer, Btr. Solvation behaviour, of amino acids has also been computed. The calculated parameters have been discussed in terms of various solute–solute and solute–solvent interactions prevailing in these solutions. Further, a detailed insight into the physicochemical interactions, e.g., ion-hydrophilic and hydrophilic–hydrophilic interactions in the amino acids in conjunction with the drug along with the structure-making/structure-breaking tendency has been retrieved through the perusal of these calculated parameters.

In this work a systematic study of the effect of temperature on the apparent molar volumes and the viscosities of aqueous solutions of ethylene glycol, glycerol, meso-erythritol, xylitol, sorbitol and myo-inositol is presented. Experimental densities and viscosities of the polyol aqueous solutions were measured in the temperature range from 293.15 to 313.15 K at intervals of 5 K. The apparent molar volumes were determined as a function of composition at each temperature from experimental data. The partial volumes at infinite dilution of the polyols in aqueous solution were evaluated through extrapolation at each temperature. The relative viscosity values were adjusted by least-squares to a second order equation to obtain the viscosity B and D coefficients. The temperature dependence of the partial molar volume at infinite dilution and the viscosity B coefficient are discussed in terms of the relationship among polar and nonpolar groups and their effect on the structure of the aqueous solvent.

Apparent molar volumes ( V ϕ ) and apparent molar isentropic compression ( K ϕ , s ) of glycine, l -alanine, l -valine and l -leucine in (0.05, 0.10, 0.15, 0.20) mol·kg−1 aqueous solution of thiamine hydrochloride (thiamine-HCl) have been determined at T = (305.15, 310.15 and 315.15) K and experimental pressure p = 0.1 MPa, from the density and speed of sound measurements. The partial molar volume V ϕ o , standard partial molar volumes of transfer Δ V ϕ o for amino acids from water to aqueous thiamine-HCl, partial molar isentropic compression K ϕ , s and partial molar isentropic compression of transfer Δ K ϕ , s o have been calculated from the corresponding data. Group contributions of amino acids to partial molar volume are also determined. The pair and triplet interaction coefficients are obtained from partial molar volumes of transfer and partial molar isentropic compression of transfer. The partial molar expansibility ( ∂ V ϕ o / ∂ T ) p , second order derivative ( ∂ 2 V ϕ o / ∂ T 2 ) p have also been calculated. The parameters obtained have been used to explain the results in terms of (solute-solute)/(ion-ion), (solute-solvent) interactions, structure making and structure breaking behaviour of amino acids in aqueous thiamine-HCl solutions.

By using the volumetric properties, the solute–solvent interactions are studied in the ternary (glycine + 1-Ethyl-3-methylimidazolium hydrogen sulfate [Emim][HSO4] + water) and ( l -serine + 1-Ethyl-3-methylimidazolium hydrogen sulfate [Emim][HSO4] + water) systems. For this purpose, the apparent molar volumes, Vφ, are calculated from the experimental density data. To obtain limiting apparent molar volumes Vφ0, the apparent molar volume values are fitted to the Redlich-Mayer type equation. Then the limiting apparent molar volumes of transfer, ΔVφ0, for studied amino acids from water to aqueous solutions of ionic liquid (IL) are calculated. The results showed that the ΔVφ0 values are negative for both ternary systems at all temperatures. The limiting apparent molar expansibility Eφ0 values have been obtained from the first derivative of limiting apparent molar volumes with respect to temperature. The values of second derivative of limiting apparent molar volumes respect to temperature show the structure making or breaking ability of glycine and l -serine in studied IL aqueous solutions. The results indicated that glycine and l -serine act as structure maker in studied solutions. McMillan–Mayer theory is used for evaluating the interaction parameters. Also the hydration number, nH, for both amino acids in ternary solutions has been reported.

The aim of this paper is to provide insight into the molecular mechanisms of inclusion complex formation along with the structural understanding of drug–carrier molecule interactions in aqueous ternary systems including caffeine and β -cyclodextrin. Apparent partial molar volumes ( V φ ) were determined from density experimental measurements for the binary aqueous solutions of both β -cyclodextrin and caffeine, as well as for the ternary aqueous solutions in the low concentration range (i.e., corresponding to the therapeutic applications in the drug-releasing field). Mathematical modelling of this apparent molar property, assuming inclusion complexes of 1:1 stoichiometry, allowed the estimation of the corresponding equilibrium constant. Information about the driving forces for the insertion of the caffeine into the β -cyclodextrin molecule was derived from the volume changes. Interactions between aqueous solutes and/or solute–solvent interactions taking place in the solutions were evaluated from the volumes of transfer, Δ V φ,c , and the viscosity B coefficients of transfer, ΔB , for the caffeine from water to the different aqueous solutions of β -cyclodextrin. The measurements were carried out at the standard (298.15 ± 0.01) K and the physiological (310.15 ± 0.01) K temperatures.

The experimental values of densities ( ρ ), speeds of sound ( u ) and relative viscosities ( η r ) of piperazine citrate in aqueous solution and in 0.06 mol·kg−1 of sodium chloride and d -glucose as a function of concentration have been obtained at T / K = (293.15, 303.15 and 313.15). The thermodynamic parameters such as apparent molar volume ( V ϕ ) of solute, isentropic compressibility ( κ s ) , apparent molar isentropic compressibility ( κ ϕ ) of solute, piperazine citrate in water and in aqueous solutions of sodium chloride and d -glucose have been computed using the density and speed of sound data. The limiting apparent molar volume of solute ( V ϕ 0 ) , limiting apparent molar compressibility ( κ ϕ 0 ) in binary and ternary solution have been obtained using apparent molar volume and apparent molar compressibility data. The limiting apparent molar expansivity ( E ϕ 0 ) of solute and thermal expansion coefficient ( α ∗ ) in both aqueous binary and ternary solutions has been computed. Transfer volumes ( Δ tr V ϕ 0 ) and transfer compressibilities ( Δ tr κ ϕ 0 ) of piperazine citrate from water to aqueous solutions of sodium chloride and d -glucose at different temperatures have been obtained. The Jones-Dole viscosity coefficients A , B , D , variation of viscosity B coefficient with temperature i.e. d B / d T , hydration number for aqueous solutions of piperazine citrate and in aqueous solutions of sodium chloride and d -glucose have been determined. The above parameters have been used to throw light on the various interactions occurring between binary and ternary systems.

Densities, ρ, speed of sound, u , for aqueous solutions of alkoxyalkanols like ethylene glycol mono methyl ether (EGMME), ethylene glycol mono ethyl ether (EGMEE) and ethylene glycol mono butyl ether (EGMBE) have been measured in aqueous solutions of surfactant sodium dodecyl sulphate (SDS) at temperatures T = (288.15, 298.15, 308.15 and 318.15) K have been measured. The different parameters such as apparent molar volume, limiting apparent molar volume, transfer volume, partial molar expansibility have been derived from density data to study the nature of interactions and also the aggregation behavior of surfactant with alkoxyalkanols. Experimental speeds of sound data were used to estimate apparent molar isentropic compression, limiting apparent molar isentropic compression, partial molar isentropic compression of transfer. The pair and triplet interaction coefficient have been calculated from both the properties. These parameters have been discussed in the light of ion-ion and ion-solvent interactions.

The density of {water (1) + ethylenediamine (2)} binary mixture was measured over the whole concentration range at temperatures from 274.15 to 333.15 K and at atmospheric pressure. The experimental values were used to calculate a whole number of the mixture parameters such as the excess molar volumes, molar isobaric expansions, apparent and partial molar volumes, partial molar isobaric expansions, limiting partial molar volumes and limiting partial molar isobaric expansions both of water and ethylenediamine. The extremal dependence of the partial molar volumes of the mixture components was observed; the mixture excess molar volumes were negative at all temperatures and depended weakly on temperature. The concentration dependences of the partial molar volumes of the mixture components were very similar to the dependences for aqueous mixtures of the nonelectrolytes with hydrophobic properties. The mixture molar isobaric expansion increased with ethylenediamine concentration over the whole concentration range. The concentration dependences of partial molar isobaric expansions of both water and ethylenediamine were rather complex and correlated with the mixture melting diagram.

Thermodynamic properties of solutions in binary and ternary aqueous systems which are derived from very accurate measurements of density and its changes with concentration, temperature and pressure, are examined in a detail. Precise definitions of the apparent molar volumes, the apparent molar expansibilities and the apparent molar compressibilities of components in ternary solutions are discussed. The significance of errors caused when inexact formulas are used is illustrated. It is demonstrated that in ternary solutions, an experimental procedure leading to determination of the mean apparent molar volume is superior than that based on the reduction to pseudo-binary systems. The present author proposed a new two-parameter empirical equation which correlate and predict densities in binary aqueous solutions. This equation includes densities of pure water at temperature T and two adjustable parameters which are practically independent of temperature. The expected accuracy of predicted in aqueous solutions densities makes this equation most suitable for engineering calculations.

In the present work, apparent molar volume and isentropic compression of glycine and diglycine in aqueous 1-butyl-3-methylimidazolium chloride, [C4mim][Cl] solutions have been calculated from the measured experimental data on density and speed of sound at temperature, T = (288.15, 298.15 and 308.15) K. The apparent molar volumes at infinite dilution, Vϕ0 and the apparent molar isentropic compression at infinite dilution Kϕ , S0, were also calculated. These results have been interpreted in terms of effect of temperature and concentration on interactions such as solute–solute, solute–solvent and solvent–solvent which exist in the mixtures. Furthermore, apparent molar expansivity, Eϕ0, and Hepler's constant values, ∂ E ϕ 0 ∂ T P have been evaluated to support the conclusions obtained from the volumetric and acoustic studies. The Hepler's constant values were found negative which indicating the amino acids under study are predominantly a structure breaker due to hydrophobic hydration of amino acid in aqueous [C4mim][Cl].

The densities of aqueous solutions of glycine, l -serine, l -alanine, l -proline with the ionic liquid (IL), 1-phenylpiperazinium tetrafluoroborate ([Phpi][BF4]) at the IL concentrations of (0.025, 0.055 and 0.100) mol·kg−1 have been measured at the temperatures of (298.15, 303.15 and 308.15) K. On the basis of the experimental results, the apparent molar volume (VФ), standard partial molar volume (VФ0), transfer partial molar volume (ΔtrVΦ0) and hydration number (nH) have been calculated. The hydrophilic–hydrophilic, hydrophobic–hydrophilic and hydrophobic–hydrophobic interactions are involved in the studied systems of {[Phpi][BF4] + amino acids + H2O. These volumetric parameters can help to understand the mixing effects and other complex biological processes between amino acids and ionic liquid aqueous solution.

Density ( ρ ) and speed of sound ( u ) values are measured for the binary mixture of 1-butyl-3-methylimidazolium tetrafluoroborate and N-methylaniline over the entire range of mole fraction at temperatures from T = (293.15 to 323.15) K under atmospheric pressure. Using the basic experimental data, molar volume, isentropic compressibility, molar isentropic compressibility, inter molecular free length, excess molar volume, excess isentropic compressibility, excess molar isentropic compressibility and excess intermolecular free length values are calculated. The partial molar volumes and partial molar isentropic compressibilities at infinite dilution have also been calculated. The trends of variation of the parameters have been interpreted in light of the solute-solvent interactions occurring in the system. The excess values are fitted to Redlich-Kister polynomial equation to estimate the binary coefficients and standard deviation between the experimental and calculated values. Further, the molecular interactions in the binary mixture system are analysed using the experimental FT-IR spectrum recorded at room temperature.

Study of hydration behavior of solute is required to understand the role of water in taste mechanisms, and the effect of additive on basic taste quality of solute. In this regard, apparent molar volume, apparent specific volume, apparent molar isentropic compressibility and apparent specific isentropic compressibility of Glu in aqueous solutions of 3-hydroxypropylammonium acetate (3HPAAc) have been determined at 293.15 K to 318.15 and at atmospheric pressure from experimentally measured density, ρ and speed of sound, u data. Derived parameters such as infinite dilution partial molar volumes, V2°, partial molar isentropic compressibilities, volume of transfer, expansion coefficients, hydration numbers, and interaction coefficients were also determined to discuss various interactions occurring between solute and cosolute in aqueous solutions. The effect of cationic and anionic moiety of 3HPAAc on the basic taste behavior of Glu has also been studied on the basis of apparent specific volume and apparent specific isentropic compressibility.

In this work, densities and speeds of sound have been measured for l -serine and l -threonine in aqueous solutions of nicotinamide at T = (288.15, 298.15, 308.15, 318.15) K and atmospheric pressure. The apparent molar volume (Vϕ), the limiting apparent molar volume (Vϕο) and limiting apparent molar volumes of transfer (ΔVϕο) for amino acids from water to aqueous nicotinamide have been calculated from density data. The limiting apparent molar expansibilities have also been calculated. Apparent molar isentropic compression (Kϕ , s), limiting apparent molar isentropic compression (Kϕ , sο) and limiting apparent molar isentropic compression of transfer (ΔKϕ , sο) have been calculated from speed of sound data. The pair and triplet interaction coefficients are obtained from limiting apparent molar volumes of transfer and limiting apparent molar isentropic compression of transfer. The present study deals with the structure-making and breaking behavior of l -serine and l -threonine in aqueous nicotinamide solutions.

Density (ρ) and sound velocity (u) measurements were carried for aqueous solutions of sodium cyclamate (SC) from 293.15 to 318.15 K. Apparent molar and specific volumes, isentropic apparent molar compressibility and hydration numbers were computed from the experimental measurements. Apparent molar volumes (Φ V ) of SC show negative deviations from the Debye–Huckel limiting law and the values obtained for Φ V at given temperatures and concentrations were used as a direct measure of the ion–ion and ion–solvent interactions. Interactions causing a sweet taste require a specific volume to stimulate receptor sites from water and possibly also in the biophase. Furthermore, the partial molar expansibility (Φ ° ), Hepler’s constant (∂2 Φ ° /∂T 2 ) and thermal expansion coefficient have been estimated. This study will help to elucidate the structural interactions of SC with water and its taste in foods.

The apparent molar volumes, isentropic compressibility coefficient, and partial molar expansibilities of N-Methylglycine and d -Glucose in aqueous environments from measurements of the densities, speeds of sound and refractive indices at different temperatures from (298.15 to 323.15) K are reported. The experimental results of thermophysical properties are obtained in a mole fraction range from (0.0018 to 0.0189) for N-Methylglycine and of (0.0037, 0.0075, 0.0115, and 0.0157) for d -Glucose solutions. The refractive indices data were analyzed based on the Lorentz–Lorenz equation. The standard isentropic compressibility and standard partial molar volumes were determined by extrapolation to infinite dilution. From the temperature dependence of solutes partial molar volumes, the partial molar expansivity, the isobaric thermal expansion coefficient, and the Hepler constant values as second derivative of infinite dilution of partial molar volume with temperature have been estimated. The variations of these thermophysical properties with concentration and temperature suggest the effects of N-Methylglycine and d -Glucose in aqueous mixtures by solute–solvent interactions.