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1.
Densities of the binary mixtures of diethylcarbonate with benzene and substituted benzenes, namely toluene, bromobenzene, chlorobenzene and nitrobenzene have been measured as a function of the composition, at 293.15 K and atmospheric pressure using a bicapillary pycnometer with an accuracy of 4 parts in 104.The calculated excess molar volumes, V E were correlated with Redlich-Kister equation. The excess molar volumes are negative over the entire range of composition for the systems diethylcarbonate with benzene, toluene, bromobenzene and nitrobenzene. An inversion of the sign of V E is observed over some concentration for mixtures of diethylcarbonate with chlorobenzene. Partial molar volumes, Vi are also evaluated and their values have been extrapolated to zero concentration to obtain the limiting value at infinite dilution, Vo i . The numerical values of the excess molar volumes for binary mixtures decrease in the order: chlorobenzene > benzene > bromobenzene ≈ toluene > nitrobenzene. The results are explained in terms of dissociation of the self-associated solute molecules and the formation of aggregates between unlike molecules.  相似文献   

2.
The excess volumes of mixing of cyclohexylamine with n-hexane, n-heptene, n-octane, n-nonane, benzene, toluene, nitrobenzene, chlorobenzene and bromobenzene have been measured at 30°C. For all systems except for n-hexane, V E is positive over the entire mole fraction range. For the n-hexane mixtures, a sigmoid curve is obtained with negative V E at high mole fraction of amine.  相似文献   

3.
The excess volume of mixing as a function of composition has been measured at 30°C and 40°C for mixtures of propylene carbonate with nitrobenzene, chlorobenzene, benzene, toluene, cyclohexane, dioxane, carbon tetrachloride, and chloroform. The highly polar nitrobenzene forms an ideal mixture with propylene carbonate. Chloroform, carbon tetrachloride, dioxane, chlorobenzene, benzene, and toluene give negative volume changes on mixing. In mixtures with cyclohexane,V m E is positive at lower mole fractions of cyclohexane but becomes negative as the mole fraction of cyclohexane increases.  相似文献   

4.
Abstract

Viscosities of binary mixtures of tetrachloroethylene with hexane, heptane, cyclohexane, methylcyclohexane, toluene, chlorobenzene, bromobenzene and nitrobenzene were measured at 303.15 K. The values of ηE are negative in all the systems except in tetrachloroethylene + bromobenzene system. An inversion in sign from positive to negative is observed in the system, tetrachloroethylene + bromobenzene. The viscosity data were analysed in terms of absolute reaction rate and free volume theories of liquid viscosity. Further, Grunberg and Nissan Parameter has also been evaluated.  相似文献   

5.
Volume changes on mixing for the binary systems formed by chlorobenzene with 1,2-dichloroethane, 1,1,1-trichloroethane and 1,1,2,2-tetrachloroethane, and by bromobenzene with 1,2-dichloroethane, 1,1,1-trichloroethane and 1,1,2,2-tetrachloroethane, have been measured as functions of composition at 303.15 and 313.15 K. The measured excess volumes are positive over the entire range of composition for the binary systems chlorobenzene + 1,2-dichloroethane and bromobenzene + 1,2-dichloroethane at 303.15 K, and for chlorobenzene + 1,1,2,2-tetrachloroethane at 313.15 K. The measured volumes VE are negative over the entire composition range for the remaining systems, except for the system chlorobenzene + 1,1,2,2-tetrachloroethane at 303.15 K, where an inversion of the sign of VE is observed over part of the concentration range.  相似文献   

6.
Molar excess volumes of mixing VE for binary mixtures of furfuryl alcohol with the aromatic hydrocarbons benzene, toluene, ethylbenzene, and o-, m-, and p-xylene were determined for the entire composition range at 25°C. VE was negative for the mixtures containing benzene, toluene and pxylene but positive for mixtures containing ethylbenzene and o- and m-xylene. The results are discussed in terms of specific interaction present in the binary mixture and are compared with those previously reported for tetrahydrofuran, fur an or furfural binary mixtures with aromatic hydrocarbons.  相似文献   

7.
Bubble temperatures at 94.7?kPa, for the binary mixtures formed by methylethylketone (MEK) with cyclo-hexanone, tetrahydrofuran, ortho- and meta-xylenes, bromobenzene, chlorobenzene, epichlorohydrin, nitrobenzene, and iso- and tert-butanols have been measured by means of a Swietoslawski-type ebulliometer. The data could be represented well by the Wilson model.  相似文献   

8.
Abstract

New experimental sound velocity and density data for binary mixtures of N-methyl-cyclohexylamine with benzene, toluene, o-xylene, m-xylene, p-xylene, chlorobenzene, bromobenzene and nitrobenzene at 303.15K have been reported. The sound velocity data were also used to compute the isentropic compressibilities (Ks ). The deviation in isentropic compressibilities (ΔKs ) from ideal behaviour suggests that the existence of weak dipole-induced dipole and dipole-dipole interactions between unlike molecules.  相似文献   

9.
The reaction of H2PtClσ with benzene, toluene, ethylbenzene, xylenes, anisole and chlorobenzene affords the new anionic σ-aryl complexes of PtIV. In the cases of monosubstituted benzenes mixtures of meta- and para-platinated isomers were prepared. No examples of the ortho-isomer were found. These complexes are intermediates in the chlorination and dimerization of aromatic compounds by H2PtClσ.  相似文献   

10.
Densities, viscosities and ultrasonic speeds of sound for binary mixtures of 1,2-dimethoxyethane (DME) with benzene, toluene, chlorobenzene, benzyl chloride, benzaldehyde, nitrobenzene, and aniline are reported over the entire composition range at ambient pressure and temperature (i.e., T=298.15 K and p=1.01×105 Pa). These experimental data were utilized to derive the excess molar volumes (VmEV_{\mathrm{m}}^{\mathrm{E}}), excess viscosities (η E), and various acoustic parameters including the deviation in isentropic compressibility (Δκ S ), internal pressure (π I), and excess enthalpy (H E). From the excess molar volumes (VmEV_{\mathrm{m}}^{\mathrm{E}}), the excess partial molar volumes ([`(V)]m,1E\overline{V}_{\mathrm{m},1}^{\mathrm{E}} and [`(V)]m,2E\overline{V}_{\mathrm{m},2}^{\mathrm{E}}) and excess partial molar volumes at infinite dilution ([`(V)]m,10,E\overline{V}_{\mathrm{m},1}^{0,\mathrm{E}} and [`(V)]m,20,E\overline{V}_{\mathrm{m},2}^{0,\mathrm{E}}) were derived and discussed for each liquid component in the mixtures. The excess/deviation properties were found to be either negative or positive, depending on the molecular interactions and the nature of the liquid mixtures.  相似文献   

11.
The equimolar mixtures of typical lanthanide shift reagents such as Eu(fod)3, Pr(fod)3 or Yb(fod)3 with silver trifluoroacetate, previously used to induce paramagnetic shifts in the 1H NMR spectra of alkenes, have been successfully applied to simple aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylenes. In benzene and p-xylene the signals of all the aromatic protons are shifted identically. In other substituted benzenes the magnitude of the induced shift depends on the distance between the proton and the substituents. In addition, the different behaviour of the signals of the methyl groups in meta-and para-xylene on the addition of the complex shift reagent allows the quantitative analysis of the two xylenes in their mixtures.  相似文献   

12.
Bubble point measurements (at 95.6 kPa) over the entire composition range are carried out for the binary mixtures formed by 1-hexanol with the: nitro-compounds (acetonitrile, acrylonitrile N,N-dimethyl formamide and aniline) and substituted benzenes (o-xylene, chlorobenzene, and nitrobenzene), employing a Swietoslawski type ebulliometer. Wilson model is found to represent the measured liquid phase composition versus bubble point temperature data well. Computed values of the vapor phase mole fractions and liquid phase activity coefficients are tabulated and briefly discussed.  相似文献   

13.
Density and refractive index have been measured for the binary mixture of dimethyl sulphoxide (DMSO) with propanoic acid and n-butyric acid at three temperatures, 293, 303 and 313 K, over the entire composition range. Excess parameters such as excess molar volume (V E) and molar refraction deviation (ΔR m) have been calculated from the measured density and refractive index to study the molecular association between the component molecules. The V E and ΔR m values of these mixtures were fitted to the Redlich–Kister polynomial equation. Both excess parameters were plotted against the mole fraction of DMSO over the whole composition range. The values of V E and ΔR m have been found to be negative for both mixtures over the entire composition range, which suggests the presence of strong intermolecular interaction. The experimental refractive data of these mixtures were also used to test the validity of the empirical relations for the refractive index.  相似文献   

14.
The densities (ρ), viscosities (η), sound speeds (u) and refractive indices (n D) of seven ternary mixtures of cyclic ether (tetrahydrofuran), methanoland cyclic compounds; benzene, toluene, chlorobenzene, nitrobenzene, anisole, cyclohexane and cyclohexanone are determined over the entire range of composition at 298.15?K. From the experimental observations, viscosity deviation (Δη), the viscous synergy and antagonism, synergic and antagonic index are derived by the equations developed by Kalentunc-Gencer and Peleg [G. Kalentunc-Gencer and M. Peleg, J. Texture Stud. 17, 61 (1986)] and Howell [N.K. Howell, Presented at the Proceedings of the Seventh International Conference, Wales, 1993], respectively. Excess molar volume (V E), excess isoentropic compressibility (ΔK S) and excess molar refraction (ΔR) have been calculated from the experimentally measured density, sound speed and refractive index values. The excess Gibb's free energy of activation (ΔG E) has also been calculated. The results are discussed and interpreted in terms of molecular package and specific interaction predominated by hydrogen bonding.  相似文献   

15.
The excess volume V E of binary mixtures of octanol, nonanol and dodecanol in ethylbenzene have been calculated from the densities measured with a vibrating tube densimeter at temperatures from 50 to 100 °C and at pressures from 0.1 to 7.5 MPa. The values of V E are positive for all the three mixtures in the complete temperature, pressure and mole fraction ranges studied. The maxima in V E is observed at 0.4 mole fraction of alkanol. The results are discussed in terms of specific interactions present in the binary mixtures. The second order thermodynamic quantities (V E /T)p,(V E /P)T and (V E /P)T which have been derived from the effect of temperature and pressure on V E , indicate an overall net creation of order in the binary mixtures of ethylbenzene with higher homologues of alkanols.  相似文献   

16.
The excess molar enthalpies H m E for the binary mixtures of furfural with the aromatic hydrocarbons namely benzene, toluene, ethylbenzene and o-, m-, and p-xylenes were determined at 35°C. The values for all the mixtures studied are positive over the entire range of composition and follow the order: o-xylene>m-xylene>ethylbenzene>p-xylene>benzene>toluene. The results are discussed in terms of the unlike specific interactions present in the binary mixtures.  相似文献   

17.
Excess molar volumes (V E), viscosities, refractive index, and Gibbs energies were evaluated for binary biodiesel + benzene and toluene mixtures at 298.15 and 303.15 K. The excess molar volumes V E were determined from density, while the excess Gibbs free energy of activation G*E was calculated from viscosity deviation Δη. The excess molar volume (V E), viscosity deviation (Δη), and excess Gibbs energy of activation (G*E) were fitted to the Redlich-Kister polynomial equation to derive binary coefficients and estimate the standard deviations between the experimental data and calculation results. All mixtures showed positive V E values obviously caused by increased physical interactions between biodiesel and the organic solvents.  相似文献   

18.
Densities (ρ), speeds of sound (u), and isentropic compressibilities (k S) of binary mixtures of dimethyl sulfoxide (DMSO) with water, methanol, ethanol, 1-propanol, 2-propanol, acetone and cyclohexanone have been measured over the entire composition range at 293.15 and 313.15 K. The excess molar volumes (V E), the deviations in speed of sound (u E) and the deviations in isentropic compressibility (k S E) have been determined. The V E, u E and k S E values were fitted by the Redlich-Kister polynomial equation and the A k coefficients as well as the standard deviations (d) between the calculated and experimental values have been derived. The results obtained are discussed from the viewpoint of the existence of interactions between the components of the binary mixtures.  相似文献   

19.
Bubble points at a pressure of 94.7 kPa, over the entire composition range are measured for the binary mixtures formed by ethylbenzene with: 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, trichloroethylene, tetrachloroethylene, chlorobenzene, and nitrobenzene making use of a Swietoslawski type ebulliometer. The liquid phase composition versus temperature measurements are found to be well represented by the Wilson model.  相似文献   

20.
Excess volumes of V E of binary liquid mixtures of quinoline with each of the nitroalkanes have been measured at 30°C as a function of composition using a continuous dilution dilatometer. The excess volumes are negative over the whole mole-fraction range for all the mixtures except quinoline + nitromethane, which exhibits positive V E over the whole range. V E results have been analyzed in the light of the Prigogine-Flory-Patterson theory, which divides V E into three contributions. The agreement between experimental and theoretical values is reasonably good.  相似文献   

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