Surface Tension of Ternary Liquid Mixtures

Abstract

Surface tension has been measured by the differential capillary rise method for three ternary mixtures containing alkanes (hexane + cyclohexane+benzene, pentane + hexane + benzene and cyclohexane + heptane + toluene at 298.15\pm 0.1°K). The sign and magnitude of the excess surface tension and excess volume depend ultimately upon the chain length of the component of the mixtures. The results of the surface tension were compared with theoretical values obtained from Flory theory, Sanchez method, Brock-Bird relation and volume fraction statistics. There is reasonable agreement between theory and experiment.     

Viscosity of ternary liquid mixtures

Viscosities of ternary liquid mixtures containing benzene + cyclohexane + carbon tetrachloride and the three possible binary combinations were measured at 25°C, and the excess viscosities were computed. Theoretical expressions for viscosity were developed on the basis of the Flory theory, the significant structure theory and a theory based on a method of estimating the properties of multi-component systems from those of binary systems. Reasonable agreement between experimental and theoretical viscosities is found.     

Viscosities of quaternary liquid solutions

Viscosity of quaternary non-electrolyte solution carbon tetrachloride+ cyclohexane+benzene+toluene has been experimentally determined at 25°C. Experimental results of viscosity have been analyzed in the light of PFP theory and BAB method. A comparative study of the two approaches has been made. Excellent agreement between theoretical and experimental findings is achieved.     

Nonlinear dielectric effect in benzonitrile and lauronitrile solutions

The nonlinear dielectric effect, NDE, and the calculated correlation factors R^p and R^s are reported for binary solutions of benzonitrile and lauronitrile in benzene and cyclohexane. Substantial differences found for solutions in these two solvents have been explained in terms of critical phenomena in cyclohexane solution.     

Thermodynamic Properties of Multicomponent Liquid Mixtures

Considering a ternary liquid mixture to be made up of three binary mixtures, by means of cell model using Sutherland type potential function for pair interaction between molecules, a statistical theory for binary liquid mixtures has been extended for ternary systems. In the light of above extension, excess volume ( V E ), excess energy ( E E ) and excess entropy ( TS E ) have been computed for three binary (benzene + cyclohexane, benzene + chlorobenzene and cyclohexane + chlorobenzene) and the resultant ternary system (benzene + cyclohexane + chlorobenzene) at 298.15 K. All the above mentioned excess properties have been computed from the data of ultrasonic velocity and density only.     

The Synthesis and Liquid-Crystal Transition Temperatures of Some Fluoro-Substituted Benzonitriles

Various laterally fluoro-substituted benzonitriles have been prepared containing a trans-4-(n-alkyl)cyclohexane ring linked to the 4-position of the benzonitriles either through a methyleneoxy (? CH₂O–) or an ethylene (? CH₂CH₂-) bridge. The bridging group links the benzonitrile and cyclohexane rings either directly or through an additional 1,4-bonded cyclohexane or benzene ring. The synthesis and liquid-crystal transition temperatures of these new compounds are described. In several cases the nematic-isotropic transition temperatures of F-substituted benzonitriles are found to be higher than those of the non-laterally substituted analogues.     

Application of the Prigogine-Flory-Patterson theory part III. Mixtures of a bicyclic compound,benzene, cyclohexane,n-hexane with a cycloalkane,cyclohexene, a cycloalkadiene and benzene

The Prigogine-Flory-Patterson theory of liquid mixtures has been qpplied to the H _m ^E and V _m ^E for binary mixtures of a bicyclic compound, benzene, cyclohexane and n-hexane with a cycloalkane, cyclohexene, a cycloalkadiene and benzene. Furthermore the Prigogine-Flory theory has been used to predict activity coefficients at infinite dilution from the experimentally determined H _m ^E at 25°C for the mixtures cyclohexane, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene and benzene with a bicyclic compound. The predictions are compared to experimental results.     

Thermochemical investigations of nearly idial binary solvents. 6. Solubilities of iodine and benzil in systems of nonspecific interactions

Solubilities have been determined at 25°C for iodine in binary mixtures of carbon tetrachloride with cyclohexane, n-hexane, n-heptane, and octamethylcyclotetrasiloxane (OMCTS) and in mixtures of cyclohexane with n-hexane and OMCTS; and for benzil in binary mixtures of carbon tetrachloride with cyclohexane, n-hexane, and n-heptane, mixtures of n-hexane with cyclohexane and n-heptane, and mixtures of benzene with cyclohexane and toluene. With the exception of the benzene+cyclohexane system, the nearly ideal binary solvent model predicts these solubilities with a maximum deviation of 6% and an overall standard deviation of 2.4%. The model correctly predicts minima for solubility (mole fraction) of iodine in the OMCTS systems, and predicts solubilities within 4% for benzil in the carbon tetrachloride+n-hexane system, in which the solubility changes by a factor of 14. The failure of the model for predicting solubilities of benzil in mixtures of benzene and cyclohexane (maximum error of 25% for and 18-fold range of solubilities) is possibly due to specific interactions between benzil and benzene.     

A Comparative Study of the PFP and BAB Models in Predicting the Surface and Transport Properties of Liquid Ternary Systems

Measurements of the surface tension, viscosity and density were carried out for three ternary and their nine contributing binary liquid systems, namely: (1) toluene + cyclohexane + carbon tetrachloride and its contributing binaries (toluene + cyclohexane), (cyclohexane + carbon tetrachloride), and (carbon tetrachloride + toluene); (2) benzene + cyclohexane  + toluene and its contributing binaries (benzene + cyclohexane), (cyclohexane  + toluene), and (toluene + benzene); and (3) carbon tetrachloride + cyclohexane + benzene and its contributing binaries, (carbon tetrachloride + cyclohexane), (cyclohexane + benzene) and (benzene + carbon tetrachloride), all at 298.15 K over a wide range of compositions. The surface and transport properties of these liquid ternary systems were also studied theoretically by two liquid models, those of PFP (Prigogine-Flory-Patterson) and BAB (Bertrand-Acree-Bruchfield). The excess surface thermodynamic and excess transport properties predicted with the use of these two models agree well with the experimental results. An attempt has also been made to explain the nature of the molecular interactions and forces involved in these liquid ternary systems.     

Interaction of cyclopentane with benzene,carbon tetrachloride and cyclohexane

Heats of mixing cyclopentane + benzene, + carbon tetrachloride, + cyclohexane at 308.15 K and for cyclohexane + carbon tetrachloride at 298.15 K have been determined in an adiabatic calorimeter. The data have been examined for current theories (McGlashan, Flory and Barker) of solutions and show that McGlashan's theory predicts values for H^E and G^E that are in good agreement with their corresponding experimental values. Interaction energy between the components of these mixtures has also been determined.     

Ultrasonic behaviour of methyl methacrylate+hydrocarbon mixtures at 298.15 and 308.15 K

The excess isentropic compressibilities, K_s^E for seven binary mixtures of methyl methacrylate+benzene, +o-xylene, +m-xylene, +p-xylene, +toluene, +ethylbenzene and +cyclohexane were estimated from the measured densities and speeds of sound at 298.15 and 308.15 K. The K_s^E values were large and positive for MMA+cyclohexane and +m-xylene, while they were negative for other mixtures. A qualitative analysis of K_s^E values was made in terms of molecular interactions. The speeds of sound of all the mixtures were also predicted from the free length theory (FLT) and collision factor theory (CFT).     

Triplet state dipole moments of aminobenzonitriles

The triplet state dipole moments mu(T) of a series of 4-amino- and 3-aminobenzonitriles in cyclohexane, benzene, and 1,4-dioxane are recalculated from previously published [J. Phys. Chem. 1992, 96, 10809] time-resolved microwave conductivity data, on the basis of newly measured intersystem crossing yields. For 4-(dimethylamino)benzonitrile (DMABN), the following values are now determined for mu(T): 8.3 D (cyclohexane), 8.9 D (benzene), and 9.7 D (1,4-dioxane), as compared with the previously reported dipole moment of 12 D for the first and the last solvent. With the other aminobenzonitriles, similar mu(T) data are obtained, between 6.9 D for 4-aminobenzonitrile (ABN) in n-hexane and 10.0 D for 4-(di-n-decylamino)benzonitrile (DDABN) in 1,4-dioxane. The increase of mu(T) observed for all aminobenzonitriles when going from cyclohexane via benzene to 1,4-dioxane may indicate that their triplet dipole moments become larger with increasing solvent polarity. The present mu(T) of DMABN, between 8.3 and 9.7 D, although larger than the ground state dipole moment mu(0) of 6.6 D, is somewhat smaller than that of the locally excited (LE) state (9.9 D) but considerably smaller than the dipole moment of the intramolecular charge transfer (ICT) state (17 D). By comparing these mu(X) data with the frequency (CN) of the cyano vibration in each state, it appears that at least for DMABN in the triplet state (CN) is not a reliable indication of the extent of charge transfer as compared with the other states S0, LE, and ICT.     

Apparent Dipole Moments of 1-Butanol, 1-Propanol, and Chlorobenzene in Cyclohexane or Benzene, and Excess Molar Volumes of (1-Propanol or Chlorobenzene + Cyclohexane or Benzene) at T = 298.15K

Apparent dipole moments and relative permittivities of {x1-butanol + (1 – x) cyclohexane}, {x1-propanol + (1 – x)cyclohexane or (1 – x)benzene} and {xchloro- benzene + (1 – x)cyclohexane or (1 – x)benzene} were determined for the mole fraction range of 0.0003 < x < 0.1 at a temperature of T = 298.15 K and at a frequency of f = 100 kHz. The apparent dipole moments were calculated using Frohlich equation. The molar excess volumes for {x1-propanol + (1 – x)cyclohexane or (1 – x) benzene} and {xchlorobenzene + (1 – x)cyclohexane} were determined by a vibrating-tube densimeter at T = 298.15 K.     

Solubilities of isobutane in methanol + benzene,methanol + cyclohexane and benzene + cyclohexane mixed solvent solutions at 298 K and 40–102 kPa

The solubilities of isobutane at pressures from 40 to 102 kPa and a temperature of 298.15 K are presented for three mixed solvent solutions: methanol + benzene, methanol + cyclohexane, and benzene + cyclohexane.     

Photoluminescence studies of iodobis-(tricyclohexylphosphine)copper(I) and iodobis-(tricyclohexylphosphine)copper(I) benzene solvate

Two newly prepared complexes were found to exhibit strong solid state emission behavior. The complexes are iodobis-(tricyclohexylphosphine)copper(I) and iodobis-(tricyclohexylphosphine)copper(I) benzene solvate. To understand the emission behavior of these complexes, density functional theory (DFT) calculations were employed. These calculations allowed the identification of major atomic contributions to HOMO, LUMO and LUMO+n orbitals. The excitation mechanism was found to be a combination of ligand to metal charge transfer (LMCT) and metal to ligand charge transfer (MLCT), with the dominance of the former. The emission lifetimes were also investigated and the decays of the complexes were found to be a bi-exponential in both methanol and cyclohexane.     

Enthalpies of mixing of binary and ternary mixtures containing diisopropylether,benzene and cyclohexane at 303.15 K

Enthalpies of mixing H have been measured for liquid binary mixtures of diisopropylether (DIPE)+benzene or cyclohexane and for liquid ternary mixtures diisopropylether+benzene+cyclohexane at 303.15 K and constant pressure using a C80 calorimeter. A Redlich-Kister type equation was used to correlate experimental results.     

Détermination des enthalpies de mélange de non-electrolytes á l'aide du microcalorimétre picker á écoulement continu

The performance of the Picker dynamic-flow microcalorimeter, which is able to scan and record (in 20 min) the enthalpy of mixing directly as a function of concentration, has been investigated at 298.15 K by measuring the three standard systems: cyclohexane + n-hexane, benzene + cyclohexane and carbon tetrachloride + benzene. Results agree to within better than 1%, in a large central range of concentration with the most reliable published data.     

Correlation of the prigogine-flory theory with isothermal compressibility data. I. Systems with quasi-spherical molecules

The isothermal compressibilities K_T for cyclohexane + benzene, cyclohexane + toluene and benzene + toluene systems at 25, 35, 45 and 60°C have been used to test the Prigogine-Flory theory using Van der Waals and Lennard-Jones energy potentials. Flory's energy parameter X ₁₂ was calculated for these systems at the four temperatures. From X ₁₂ for the equimolar mixture, the following excess functions were calculated: (?V^E/?_p)_T which is related to K _T ^E , the heat of mixing H ^E , and the excess volume V ^E . The theory and any of the two potentials give (?V^E/?_p)_T which fit the experimental data, but H ^E and V ^E , calculated using the same X ₁₂ parameter, depart appreciably from the experimental data even though they agree in sign and have the essential features of the excess functions. The departure is apparent in both magnitude (in particular for the cyclohexane + benzene, and cyclohexane + toluene systems) and in the temperature dependence. The conclusion is that the X ₁₂ parameter does not predict the thermodynamic properties of these systems and the Lennard-Jones potential, involving a more complicated expression, does not contribute any improvement over the Van der Waals potential.     

Molar excess heat capacities and volumes for mixtures of benzonitrile with cyclohexane between 10 and 45°C

The heat capacities and volumes for binary mixtures of benzonitrile with cyclohexane were determined at 10, 25, and 45°C. The dependence of the molar excess heat capacities on temperature and composition are interpreted in terms of the thermal relaxation of associated benzonitrile molecules into monomeric species.To whom correspondence should be addressed.