Excess volumes for binary liquid mixtures of trichloroethylene with anisole,pyridine, quinoline and cyclohexane at 298.15 and 308.15 K

Dilatometric measurements of excess volumes V^E have been made for binary liquid mixtures of trichloroethylene (CHClCCl₂) with anisole, pyridine, quinoline and cyclohexane at 298.15 and 308.15 K. At both temperatures, and values of V^E have been found to be slightly negative for CHClCCl₂ + anisole, CHClCCl₂ + pyridine, highly negative for CHClCCl₂ + quinoline, and highly positive for CHClCCl₂ + cyclohexane. The negative values of V^E for the systems CHClCCl₂ + anisole, CHClCCl₂ + pyridine, and CHClCCl₂ + quinoline, have been explained as due to the existence of specific interaction of CHClCCl₂ with anisole, pyridine and quinoline in the liquid state.     

Molar heat capacity of binary liquid mixtures: 1,2-dichloroethane + cyclohexane and 1,2-dichloroethane + methylcyclohexane

The molar heat capacity at constant pressure, C_P, of the two binary liquid mixtures 1,2-dichloroethane + cyclohexane and 1,2-dichloroethane + methylcyclohexane were determined at 298.15 K from measurements of the volumetric heat capacity, C_P/V, in a Picker flow microcalorimeter (V is the molar volume). For the molar excess heat capacity, C_P^E, the imprecision of the adopted stepwise procedure is characterized by a standard deviation of about ± 0.05 J K^?1 mole^?1, which amounts to ca. 3% of C_P^E. Literature data on ultrasonic velocities, on molar volumes, and on coefficients of thermal expansion were used to calculate the molar heat capacity at constant volume, C_v, and the isothermal compressibility, β_T, of the pure substances, as well as the corresponding excess quantities C_V^E and (Vβ_T)^E of the binary mixture 1,2-dichloroethane + cyclohexane. A preliminary discussion of our results in terms of external and internal rotational behavior (trans-gauche equilibrium of 1,2-dichloroethane) is presented.     

Excess molar volumes of the binary mixtures of polyethylene glycol 300 with ethoxyethanols at various temperatures

Densities at T = (293.15, 298.15, 303.15, 308.15, and 313.15) K in the binary liquid mixtures of polyethylene glycol 300 with 2-ethoxyethanol, 2-(2-ethoxyethoxy)ethanol, or 2-{2-(2-ethoxyethoxy)ethoxy}ethanol have been measured over the entire range of mixture compositions. These data have been used to compute the excess molar volumes. The excess molar volumes are negative over the entire range of composition for all studied mixtures. The results are discussed in terms of intermolecular interactions in the bulk binary mixtures.     

Thermodynamics of binary mixtures: excess volumes of mixing of some binary 1,2-dichloroethane mixtures

The excess volumes, V^E, of some binary 1,2-dichloroethane mixtures have been determined at 30°C. The data have been examined for Cell model theory of Prigogine and Flory's theory. Both theories have been found to fail to fit the results with useful accuracy.     

Excess molar volumes and viscosities of binary mixtures of cyclohexane and n-alkane at 298.15 K

Awwad, A.M. and Salman, M.A., 1986. Excess molar volumes and viscosities of binary mixtures of cyclohexane and n-alkane at 298.15 K. Fluid Phase Equilibria, 25: 195-208.Excess molar volumes, viscosities, excess molar viscosities, and excess molar activation energies of viscous flow were determined for binary mixtures of cyclohexane + n-pentane, + n-hexane, + n-heptane, + n-octane, + n-nonane, + n-decane, + n-dodecane, + n-tetradecane and + n-hexadecane at 298.15 K. The effect of orientational order of n-alkane on solution molar volumes and viscosities is investigated as well as the adequacy of the Flory theory and free volume theories used to predict solution molar volumes and viscosities. For longer n-alkanes V^E, η^E and ΔG*^E are positive and associated with the orientational order.     

Excess volumes of the binary mixtures of trichloroethylene withn-alcohols at 30 and 40°C

Volumes of mixing binary systems formed by trichloroethylene with n-alcohols (1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, and 1-octanol) were measured as a function of composition at 30 and 40°C, by dilatometric measurements. All the systems show a change of sign for V ^E from negative to positive as the mole fraction trichloroethylene increases at both temperatures The positive value of the excess volumes increase as carbon chain length increases. The results are explained in terms of depolymerization of hydrogen bonded alcohol aggregates and weak hydrogen-bonding interaction of the type Cl-H–O between unlike molecules.     

Excess volumes of the binary mixtures of cyclohexane with isomers of hexanol at 25°C

The excess molar volumes V _m ^E of binary mixtures of cyclohexane with several isomers of hexanol were measured at 25°C as a function of composition using a vibrating-tube digital densimeter. For all the systems V _m ^E is positive over the entire range of mole fractions. Variable-degree polynomials have been fitted to the experimental results.     

Excess molar volumes and viscosities of binary mixtures of 1,2-diethoxyethane with chloroalkanes at 298.15 K

Excess molar volumes (V _m ^E ) and viscosities (η) of the binary mixtures of 1,2-diethoxyethane with di-, tri- and tetrachloromethane have been measured at 298-15 K and atmospheric pressure over the entire mole fraction range. The deviations in viscosities (δlnη) and excess energies of activation (δG*^E) for viscous flow have been calculated from the experimental data. The Prigogine-Flory-Patterson (PFP) model has been used to calculateV _m ^E , and the results have been compared with experimental data. The Bloomfield and Dewan model has been used to calculate viscosity coefficients and these have also been compared with experimental data for the three mixtures. The results have been discussed in terms of dipole-dipole interactions between 1,2-diethoxyethane and chloroalkanes and their magnitudes decreasing with the dipole character of the molecules. A short comparative study with results for mixtures with polyethers and chloroalkanes is also described.     

Isobaric vapour–liquid equilibria for binary mixtures of 1,2-dibromoethane with 1,2-dichloroethane,trichloromethane, and 1,1,2,2-tetrachloroethane at atmospheric pressure

Vapour–liquid equilibria at atmospheric pressure have been determined for binary mixtures of 1,2-dibromoethane + 1,2-dichloroethane, +trichloromethane, and +1,1,2,2-tetrachloroethane. These have been shown to be thermodynamically consistent.     

Compressibilities of cyclohexane and toluene mixtures at various temperatures

The isothermal compressibilities _T for cyclohexane+toluene mixtures at 25, 35, 45 and 60°C have been determined by direct piezometric measurement. By combining our results with supplementary literature data, we have calculated the isentropic compressibility _S. Values of the excess functions (V^E/_p)_T, _T ^E and _S ^E were also calculated at four temperatures and their behavior as a function of mole fraction and temperature was studied.     

Excess volumes of mixing of 1,2-dichloroethane and aromatic hydrocarbons

Excess volumes of mixing, V^E, for binary mixtures of 1,2-dichloroethane with benzene, toluene, o^?, m^?, and p-xylenes have been determined at 308.15 K over the complete composition range. V^E is positive for all these mixtures and varies in the order m-xylene >o-xylene >p-xylene > benzene > toluene. The experimental data have been analyzed in terms of the Prigogine's average potential cell model coupled with Balescu's theory. The calculated V^E values do not agree with the corresponding experimental values.     

Excess molar volumes and deviations of the relative permittivity of the binary mixtures of 2-propoxyethanol with diethylene,triethylene, and tetraethylene glycols at various temperatures

Densities and relative permittivities at T = (293.15, 298.15, and 303.15) K in the binary liquid mixtures of 2-propoxyethanol with diethylene glycol, triethylene glycol, and tetraethylene glycol have been measured over the entire mixture compositions. These data have been used to compute the excess molar volumes and deviations of the relative permittivity. The results are discussed in terms of intermolecular interactions in the bulk of studied the binary mixtures.     

Relative permittivities and refractive indices of binary mixtures of cyclohexanone with dichloromethane,trichloromethane, 1,2-dichloroethane,trichloroethene and cyclohexane at T=303.15 K

Relative permittivities, ϵ_r, and refractive indices, n_D, have been measured for binary liquid mixtures of cyclohexanone (C₆H₁₀O) with dichloromethane (CH₂Cl₂), trichloromethane (CHCl₃), 1,2-dichloroethane (CH₂ClCH₂Cl), trichloroethene (CHClCCl₂), and cyclohexane (c-C₆H₁₂) at T=303.15 K. The values of the deviations of ϵ_r and n_D from values arising from mole fraction average, which are represented respectively by Δϵ_r and Δn_D have been calculated. Values of ϵ_r and Δn_D have been fitted by the method of least squares to smoothing equations. Δϵ_r for the various mixtures has been discussed from the viewpoint of the existence of specific interactions between the components.     

Excess heat capacities and excess volumes of binary liquid mixtures of 1,1,1,-trichloroethane with cyclic ethers at 298.15 K

Measurements of volumetric heat capacities at constant pressure, C_p/V (V being the molar volume), at 298.15 K, of the binary liquid mixtures 1,1,1-trichloroethane + oxolane, +1,3-dioxolane, +oxane, +1,3-dioxane, and +1,4-dioxane were carried out in a Picker-type flow microcalorimeter. Molar heat capacities at constant pressure. C_p, and molar excess heat capacities, C^E_p, were calculated from these results as a function of the mole fraction. C^E_p values for these systems are positive and the magnitude depends on the size of the cycle and on the relative position of the oxygen atoms in the cyclic diethers. The precision and accuracy for C^E_p are estimated as better than 2%. Molar excess volumes, V^E, for the same systems, at 298.15 K, have been determined from density measurements with a high-precision digital flow densimeter. The experimental results of V^E and C^E_p, are interpreted in terms of molecular interactions.     

Excess heat capacities and excess volumes of binary liquid mixtures of chloroform with cyclic ethers at 298.15 K

Molar excess heat capacities at constant pressure, C^E_p, of binary liquid mixtures chloroform + oxolane, chloroform + 1,3-dioxolane, chloroform + oxane, and chloroform + 1,4-dioxane have been determined at 298.15 K from measurements of volumetric heat capacities in a Picker flow microcalorimeter. A precision of ±0.04 J K^?1 mole^? was achieved by using the stepwise procedure. Experimental molar excess heat capacities are compared with values derived from H^E results at different temperatures. Excess molar volumes, V^E, for the same systems at 298.15 K have been determined by measuring the density of the pure liquids and solutions with a high-precision digital flow densimeter.     

Excess volumes of binary liquid mixtures of benzaldehyde and acetophenone with hydrocarbons,carbon tetrachloride,and chloroform

Molar excess volumes of benzaldehyde and acetophenone with cyclohexane, benzene, toluene, p-xylene, chloroform, and carbon tetrachloride were measured at 25 and 35°C as a function of composition.     

Excess functions of binary liquid mixtures at varying pressures

The present investigation comprises of theoretical evaluation of the thermodynamic excess functions, viz. excess energy and excess entropy for five binary liquid mixtures at varying pressures. A statistical mechanical theory, along with the Schaaff’s equation for sound velocity was used in order to calculate the above-mentioned excess properties directly through the use of the experimental data of ultrasonic velocity and density only.