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1.

The experimental density (ρ) and the velocity (U) for ternary mixture of dimethyl acetamide diethyl ether and isobutyl methyl ketone at different frequencies (2, 4, 6 and 8 MHZ) have been measured at a constant temperature of 308 K. These data have been used to compute acoustic impedance (Z), adiabatic compressibility (K s), intermolecular free length (Lf ), molar volume (Vm ), molar sound velocity (R), molar compressibility (B), available volume (V a), Lennard-Jones potential repulsive term exponent (n), relative association (R A), interaction parameter (X) and excess values of some of the above parameters for entire range of mole fraction and are interpreted to explain molecular interaction occurring in the liquid mixture.  相似文献   

2.
The ultrasonic velocity and density have been measured at different temperatures between 299 and 363 K for the pure liquid sample, poly(ethylene glycol) with average molecular mass 400 g mol?1 (PEG 400). From these, isentropic compressibility (β), intermolecular free length (L f), acoustic impedance (Z), molar volume (V m), Schaff’s available volume V a(s), molar sound velocity (R a), and molar compressibility (W) have been evaluated. The variations of these parameters with the temperature of the sample have been studied. Data so obtained are employed to compute other thermodynamic parameters. Variations in various parameters with respect to temperature are discussed in the light of the results obtained.  相似文献   

3.
Ultrasonic velocity, density and viscosity of the ternary mixture of toluene + chloroform + cyclohexane, were measured at 303.15, 308.15, and 313.15 K. The thermodynamically parameters such as adiabatic compressibility (??), intermolecular free length (L f), free volume (V f), internal pressure (?? i ), acoustic impedance (Z), molar sound velocity (R), and molar compressibility (W) have been obtained from the experimental data for all the mixtures, with a view to investigate the exact nature of molecular interaction. Adiabatic compressibility and intermolecular free length decrease with increase in concentration and temperature. The other parameters show almost increasing concentration of solutes. These parameters have been further used to interpret the molecular interaction part of the solute and solvent in the mixtures.  相似文献   

4.
Abstract

Ultrasonic velocity of CdCl2 and KCl in co-solvent of Acetone and Water is measured at different concentrations from 298.15 K to 318.15 K using single crystal interferometer; operating at frequency of 2 MHz. Various acoustical parameters such as adiabatic compressibility (βs), specific impedance (Z), apparent molar compressibility (ØK), relative association (R A), Rao's molar sound function (R), molar compressibility (W), free volume (V f) have been calculated. Results throw light on the solute-solvent and solute-solute interactions. Effect of temperature variation on these interactions has also been discussed.  相似文献   

5.
The ultrasonic velocity (U), density (ρ) and viscosity (η) at 298.15 K have been measured in the binary systems of monosaccharides (glucose, fructose and galactose) in aqueous medium. The acoustical parameters such as adiabatic compressibility (β), free length (Lf), free volume (Vf), internal pressure (πi), acoustical impedance (Z), relative association (RA), molar sound velocity (R) and molar sound compressibility (W) are calculated. The results are interpreted in terms of molecular interaction between the components of the mixtures.  相似文献   

6.
The density (ρ), viscosity (η) and ultrasonic velocity (u) of three mixtures consisting of 2- pyrrolidone with 1,3-propanediol (PD) and water and also of PD and water have been measured as a function of mole fraction at 308.15 K. The experimentally collected data has been used to calculate the excess molar volume (VE), deviation in viscosity (Δη), deviation in ultrasonic velocity (Δu), isentropic compressibility (κs), deviation in isentropic compressibility (Δκs) and excess Gibbs free energy of activation (ΔG*E). The Redlich–Kister polynomial equation has been used to fit the derived parameters. The variation in excessive thermodynamic properties as a consequence of possible molecular interactions is discussed.  相似文献   

7.
Density, ultrasonic velocity of pure dioxane (Dx) and ligands, 4,6-dimethyl-7-hydroxycoumarin (L1), 6-ethyl-7-hydroxy-4-methylcoumarin (L2), and 3-chloro-7-hydroxy-4-methylcoumarin (L3) in different percent of Dx-water mixture have been investigated at 303.15 K. Acoustical parameters such as adiabatic compressibility (β), intermolecular free length (L f ), acoustical impedance (Z), relative association (R A ), apparent molar compressibility (Φβ), and apparent molar volume (Φ V ) have also been evaluated from the experimental data of density and ultrasonic velocity. An excellent correlation between a given parameters is observed at all percent of dioxane-water and the result suggests nature of intermolecular interactions between the components.  相似文献   

8.
The apparent molar volume (?V), viscosity B-coefficient and molar refraction (RM) have been determined of L-valine in aqueous solution of LiCl, NaCl and KCl at 298 K, 303 K and 308 K from density (ρ), viscosity (η) and refractive index (nD) measurements, respectively. The limiting apparent molar volumes (?V0) and experimental slopes (SV*) derived from the Masson equation have been interpreted in terms of solute–solvent and solute–solute interactions, respectively. The viscosity data were analysed using the Jones–Dole equation and the derived parameter B has also been interpreted in terms of solute–solvent interactions in the solutions. Molar refraction (RM) has been calculated using the Lorentz–Lorenz equation.  相似文献   

9.
The ultrasonic velocity, density and viscosity of pectin in aqueous medium were measured at 298.15 K. The acoustical parameters such as adiabatic compressibility (β), free length (L f), free volume (V f), internal pressure (πi), acoustical impedance (Z), and relative association (R A), Rao’s constant (R) and Wada’s constant (W) are calculated. The results are interpreted in terms of molecular interaction between the components of the mixtures. Further, some more acoustical parameters such as relaxation time (τ), absorption coefficient (α/f 2) and relaxation strength (r) are calculated with various percentage of pectin has been studied which reveals interaction between the solvent and the polymer (pectin) at various concentration of the polymer. The observed values suggested the solute-solvent interaction is favored.  相似文献   

10.
The density, viscosity, and ultrasonic velocity of solutions of two schiff bases in 1,4-dioxane and dimethylformamide (DMF) were measured at 318.15 K. Various acoustical properties, such as the specific impedance (Z), isentropic compressibility (κs), Rao’s molar sound function (R m), van der Waals constant (b), molar compressibility (W), intermolecular free length (L f), relaxation strength (r), relative association (R A), and free volume (V f), were calculated. The results were interpreted in terms of molecular interactions occurring in the solutions. Published in Russian in Zhurnal Fizicheskoi Khimii, 2006, Vol. 80, No. 7, pp. 1206–1210. The text was submitted by the authors in English.  相似文献   

11.
《Fluid Phase Equilibria》2004,215(1):55-59
For three derivatives of 4-amino antipyrene, density, viscosity and ultrasonic velocity are measured at 318.15 K in 1,4-dioxane (DO) and dimethylformamide (DMF). From these experimental data, various acoustical properties such as specific impedance (Z), isentropic compressibility (κs), Rao’s molar sound function (Rm), the van der Waals constant (b), molar compressibility (W), intermolecular free length (Lf), relaxation strength (r), relative association (RA), free volume (Vf), etc. and apparent molar volume and apparent molar compressibility were calculated. The results are interpreted in terms of molecular interactions occurring in the solutions. It is observed that in 1,4-dioxane solutions, solute–solute interactions exist whereas solvent–solute interactions predominant in DMF system.  相似文献   

12.
The speed of sound and density of 2-hydroxy-5-methyl acetophenone in dimethylformamide have been measured over the range of temperatures 25–40 °C. From the experimentally determined data, values of apparent molar volume (V ϕ), adiabatic compressibility (βs), apparent molar adiabatic compressibility (K s,ϕ) and their limiting values have been computed. Values at infinite dilution provide information regarding solute–solvent interaction. The density and velocity increases with increase in concentration and decreases with increase in temperature. These results have been analyzed in terms of molecular interactions between acetophenone and dimethylformamide.  相似文献   

13.
The present article reports the values of density (ρ12), molar volume (V12), apparent molar volume (V?), dielectric constant (?12), molar polarisation (P12) and molar refraction (R12) of binary mixture of di-2-ethylhexyl phosphoric acid (DEHPA) and petrofin at various compositions. The excess properties such as VE, ?E, ΔnD, PE and RE have been calculated to throw light on the existence of interaction between the DEHPA and petrofin molecules in the binary mixture. The values of VE and RE were found to be positive while the values of ?E, ΔnD and PE were negative over the entire composition showing weak interaction between the two unlike molecules in the mixture. The Kirkwood-correlation factors (g) have been evaluated to know the nature of interaction prevailing in DEHPA and petrofin. These data provide useful information regarding interaction between self-associated protic DEHPA and non-associated petrofin which in turn helps the metallurgist to use DEHPA diluted with petrofin as effective solvent in extraction of metals.  相似文献   

14.
Thermophysical properties for binary mixture of tetraethylene glycol (T4EG) (1) + 1,2-ethanediamine (EDA) (2), a potential scrubbing solution for the absorption of CO2, are very important as well as lacking in the literatures. This work reports densities and viscosities over the entire concentration range for the binary mixture at T = (293.15-318.15) K under atmospheric pressure. According to the experimental density and viscosity values, the mixtures’ excess molar volume (VmE), absolute viscosity deviation (?η), excess free energies of activation (?G*E), apparent molar volumes, partial molar volumes and isobaric thermal expansion coefficient were calculated, respectively. Meanwhile, the VmE, ?η and ?G*E values were fitted by a Redlich–Kister equation to obtain coefficients. To further study, the Fourier transform infrared, UV-Vis and fluorescence spectra of T4EG + EDA mixtures with various concentrations were measured, and the intermolecular interaction of T4EG with EDA was also discussed as the formation of –OCH2CH2O–H···N(H2)CH2CH2(H2)N···.  相似文献   

15.
Ultrasound velocity (u), density (ρ) and viscosity (η) measurements of benzaldehyde + ethylbenzene mixtures have been carried out at 303.15, 308.15, and 313.15 K. These values have been used to calculate the excess molar volume (V E), deviation in viscosity (δη), and deviation in isentropic compressibility (δβs), deviations in ultrasound velocity (δu), excess free volume (δV f), excess intermolecular free length (δL f) and excess Gibbs free energy of activation of viscous flow (δG E). McAllister’s three body interaction model is used for correlating kinematic viscosity of binary mixtures. The excess values were correlated using the Redlich-Kister polynomial equation to obtain their coefficients and standard deviations. The thermophysical properties under the study were fit to the Jouyban-Acree model. The observed variation of these parameters helps in understanding the nature of interactions in these mixtures. Further, theoretical values of the ultrasound speed were evaluated using theories and empirical relations.  相似文献   

16.
Abstract

Ultrasonic velocity (U) and density (d) have been measured for CuCl-KCl in. acetonitrile water co-solvent at various temperatures from 298.15 to 318.15K. The adiabatic compressibility (βad), molar compressibility (β) specific acoustical impedance (Z), Rao Number (R) and Van der Waals Constant (b) have been computed. The variation of d, βad, β, Z, R and b with molarity of CuCl have been studied. The association between the components and the formation of complexes are treated.  相似文献   

17.
The values of density, viscosity, and ultrasonic velocity for the binary liquid mixture of benzaldehyde with bromobenzene have been measured over the entire range of composition at 303.15, 308.15, and 313.15?K. These values have been used to calculate the excess molar volume (V E), deviation in viscosity (????), deviation in velocity (?U), deviation in isentropic compressibility (??? s), excess internal pressure (???), excess intermolecular free length (?L f), and excess acoustic impedance (?Z). McAllister??s three-body-interaction model is used for correlating kinematic viscosity of binary mixtures. The excess values were correlated using the Redlich?CKister polynomial equation to obtain their coefficients and standard deviations. The thermo-physical properties (density, viscosity, and ultrasonic velocity) under the study were fitted to the Jouyban?CAcree model.  相似文献   

18.
Densities and ultrasonic velocities were measured for binary liquid mixtures of ethyl acetoacetate (EAA) with chloroform (CHCl3) and dimethylsulphoxide (DMSO) over the entire composition range. These experimental values were used to calculate the adiabatic compressibility (βs), intermolecular free length (Lf), excess molar volume (VE), excess adiabatic compressibility (βsE) and excess intermolecular free length (LfE) for the liquid mixtures under consideration. In all the excess parameters, a positive deviation was observed in CHCl3–EAA binary mixture, whereas a slight negative deviation was found for EAA–DMSO binary liquid mixture. These deviations were explained in terms of molecular interactions between like and unlike molecules and further affirmed by UV–Vis spectroscopic measurements in terms of polar and non-polar environment in the close proximity of solvatochromic dye. Fourier transform infrared spectroscopy (FT-IR) and proton-nuclear magnetic resonance (H1 NMR) measurements have also been done to explain the molecular interaction in the binary liquid mixtures.  相似文献   

19.
Experimental measurements of the speed of sound, density and osmotic vapour pressure are reported for binary 18-Crown-6 (18C6) + CH3OH, KBr + CH3OH and ternary KBr + 18C6 + CH3OH solutions at 298.15 K. The density and compressibility data were processed to obtain the apparent molar volume (ø V ) and apparent molar isentropic compressibility ( $\phi _{K_S } Experimental measurements of the speed of sound, density and osmotic vapour pressure are reported for binary 18-Crown-6 (18C6) + CH3OH, KBr + CH3OH and ternary KBr + 18C6 + CH3OH solutions at 298.15 K. The density and compressibility data were processed to obtain the apparent molar volume (? V ) and apparent molar isentropic compressibility () of the solutes in methanol. Expansivity data were obtained for the 18C6 + CH3OH system from density data at different temperatures and were used for calculation of the isothermal compressibility values at 298.15 K. The isothermal compressibility and expansivity data are further used to obtain the apparent molar isothermal compressibility () and apparent molar expansivity (? E ) of 18C6 in methanolic solutions and as well as the energy-volume coefficient parameter (∂ U/∂ V) T in methanol solutions. The volume and compressibility changes due to complexation of KBr with 18C6 are obtained at infinite dilution for ? V and ? K . The results are compared with the similar data obtained by us previously for aqueous and CCl4 solutions. The osmotic coefficient data were used to calculate activities and activity coefficients of each component at 298.15 K as a function of the concentration of binary and ternary methanolic solutions containing KBr and 18C6. The activity and activity coefficient data are used to evaluate the pair and triplet interaction parameters by making appropriate use of the McMillan-Meyer theory of solutions. The calculation of the thermodynamic equilibrium constant (K) is made using the pair interaction parameter, g NE (non-electrolyte – electrolyte pair interaction), for the complexation equilibria. The nature of interactions present in the CH3OH solutions is discussed.  相似文献   

20.
This article reports experimental values of refractive index nD , density ρ, speed of sound u, isentropic compressibility κs, excess molar volume of mixing V E, deviations of refractive index δnD and isentropic compressibility δκs of the binary mixture n-hexane + n-alkane from T = (288.15 to 323.15) K and atmospheric condition. The corresponding excess derived property was computed from the experimental data. Parameters of analytical expressions which represent the composition dependences of the derived property are reported. Values of physical properties were compared with the results obtained by different prediction methods.  相似文献   

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