Measurements Of Excess Volumes Research Articles

Batch Dilatometer for Measurement of Excess Volumes of Ternary Mixtures and Ternary Volume Effects in Benzene-Carbon tetrachlonde-Cyclohexane Mixtures at 298.15 K

Batch Dilatometer for Measurement of Excess Volumes of Ternary Mixtures and Ternary Volume Effects in Benzene-Carbon tetrachlonde-Cyclohexane Mixtures at 298.15 K

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 (CHClCCl 2) 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 CHClCCl 2 + anisole, CHClCCl 2 + pyridine, highly negative for CHClCCl 2 + quinoline, and highly positive for CHClCCl 2 + cyclohexane. The negative values of V E for the systems CHClCCl 2 + anisole, CHClCCl 2 + pyridine, and CHClCCl 2 + quinoline, have been explained as due to the existence of specific interaction of CHClCCl 2 with anisole, pyridine and quinoline in the liquid state.

Excess volumes of binary mixtures of ethylbenzene + n-alkanes

Excess volumes of binary mixtures of ethylbenzene + n-hexane, n-octane, n-decane, n-dodecane, n-tetradecane and n-hexadecane have been determined at 298.15 K over the whole mole fraction range. A semicontinuos dilution dilatometer has been used to perform the excess volume measurements. The results have been compared with those obtained for binary mixtures of the same n-alkanes with toluene and the three xylenes.

Excess enthalpies and excess volumes of each of the mixtures: ( n-dodecane+an isomer of hexane) at 298.15 K

Calorimetric measurements of excess enthalpies and dilatometric measurements of excess volumes were carried out for each of the five mixtures: ( n-dodecane + an isomer of hexane) at 298.15 K. The Flory theory of mixtures provides a reasonable correlation of the results.

Excess volumes and isentropic compressibilities of 2,5,8-trioxanonane-n-heptane mixtures

Measurements of excess volume and ultrasonic speed were carried out for mixtures of 2,5,8-trloxanonane ((CH,0CH2CH2),0) wlth n-heptane at 298.15 K over the entire mole fraction range Including the region of high dilution of the ether. From these results, Isentropic comprerdbllltles, excess isentropic comprerdbilltles, partial molar excess volumes, and partial molar excess Isentropic compresslblllties were calculated. A qualitative discusdon of the results Is presented.

The enthalpy of mixing of (acetone + trichloromethane) vapour

Measurements of the excess enthalpy of (acetone + trichloromethane) vapour have been made using a new differential flow calorimeter. The measurements cover the range 323.3 to 393.2 K at pressures between 34.3 and 104.5 kPa. The accuracy of the measurements is ± 2 per cent. Cross-term second virial coefficients B 12 derived from the measurements are in good agreement with B 12's obtained from excess-volume measurements.

ChemInform Abstract: CRITICAL EXPONENTS FOR (METHYLCYCLOHEXANE + TETRADECAFLUOROMETHYLCYCLOHEXANE) FROM MEASUREMENTS OF EXCESS VOLUMES AT TEMPERATURES CLOSE TO THE CRITICAL MIXING TEMPERATURE

Chemischer InformationsdienstVolume 12, Issue 1 Article ChemInform Abstract: CRITICAL EXPONENTS FOR (METHYLCYCLOHEXANE + TETRADECAFLUOROMETHYLCYCLOHEXANE) FROM MEASUREMENTS OF EXCESS VOLUMES AT TEMPERATURES CLOSE TO THE CRITICAL MIXING TEMPERATURE M. K. KUMARAN, Search for more papers by this authorM. L. MCGLASHAN, Search for more papers by this author M. K. KUMARAN, Search for more papers by this authorM. L. MCGLASHAN, Search for more papers by this author First published: January 6, 1981 https://doi.org/10.1002/chin.198101089AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume12, Issue1January 6, 1981 RelatedInformation

Thermodynamics of glycerol trioleate + n-alkanes

Excess volume measurements for glycerol trioleate + n-alkanes (5 ⩽n⩽ 18) at 30 °C are compared with predictions from a corresponding states theory of oligomeric mixtures. Quantitative discrepancies between theory and experiment suggest that glcerol trioleate does not behave like a long-chain hydrocarbon in its mixtures with n-alkanes.

Excess volumes for n-alkanols + n-alkanes III. Binary mixtures of hexan-1-ol + n-pentane, + n-hexane, + n-octane, and + n-decane

Measurements of excess volumes at 298.15 K in a successive dilution dilatometer are reported for binary mixtures of hexan-1-ol with the n-alkanes C 5, C 6, C 8, and C 10. In this series of mixtures, the excess-volume curves change from sigmoid with positive values in the alkanol-rich region for mixtures with n-pentane, to positive values over the whole mole-fraction range for mixtures with n-decane. The positive region for (hexan-1-ol + n-pentane) occurs below 0.02 mole fraction of C 6H 13OH, and measurements were extended to high alkanol dilutions. Partial molar excess volumes of the components were calculated for each mixture, and their values at infinite dilution were estimated.

Critical exponents for (methylcyclohexane + tetradecafluoromethylcyclohexane) from measurements of excess volumes at temperatures close to the critical mixing temperature

Molar excess volumes of (methylcyclohexane + tetradecafluoromethylcyclohexane) have been determined as a function of composition at each of 15 temperatures from 2 K above to 1.5 K below the critical mixing temperature (319.262 K). The results have been analysed in terms of the critical exponents α, β, and γ.

Excess volumes for n-alkanols + n-alkanes II. Binary mixtures of n-pentanol, n-hexanol, n-octanol, and n-decanol + n-heptane

Measurements of excess volumes at 298.15 K in a successive dilution dilatometer are reported for binary mixtures of the n-alkanols C 5, C 6, C 8, and C 10+ n-heptane. All the excess volume curves are sigmoid but the region of positive values of the excess volume decreases markedly with increasing length of the alkanol molecule, and for n-decanol+ n-heptane is limited to mole fractions of alkanol less than 0.03. Partial molar excess volumes of the components were calculated for each mixture and their values at infinite dilution were estimated.

An improved dilution dilatometer for measurements of excess volumes

A new design of tilting dilution dilatometer is described. It is easier to calibrate, and easier to load and operate, than previous designs, and has two advantages. No liquid passes through a greased (or any) tap and no tap is opened or closed throughout a series of dilution measurements. There is no possibility of error from diffusion of one liquid into the other, the liquids always being separated by mercury. The new dilatometer has been used to make a series of measurements of the molar excess volume of benzene + cyclohexane at 298.15 K; the results compare well with those of previous measurements.

Excess enthalpies and excess volumes of 2-chlor-2-methyl-propane + benzene, + carbon tetrachloride, and + cyclohexane at 283.15 K, 293.15 K, 303.15 K and 313.15 K

Measurements of excess volume and excess enthalpy for 2-chlor, 2-methylpropane in each of the non-polar solvents : cyclohexane, benzene and carbon tetrachloride, at 10, 20, 30 and 40 °C, were made.The experimental results were treated by obtaining the dispersive contribution according to Kehiaian’s method and the specific interaction contribution by difference.

Mixing cell for indirect measurements of excess volume

A mixing cell suitable for making liquid mixtures of accurately known composition is described and has been tested by measurements of the excess volume of benzene + cyclohexane.

Excess volumes of nitroethane + 3-methylpentane

Excess volumes for nitroethane + 3-methylpentane have been measured at 298.596, 300.153, 303.150, and 313.176 K. The excess volume is positive at these temperatures, has a maximum near x(C 2H 5NO 2) = 0.25, and is unusually flat at compositions approaching pure nitroethane. The results are compared with excess volume measurements on other mixtures of nitroethane + hydrocarbon. Measurements of coexisting densities reported by Wims, McIntyre, and Hynne ( J. Chem. Phys. 1969, 50, 616) are reanalyzed and a value of the critical exponent β = 0.33 is obtained.

Excess volumes of mixing of nearly spherical molecules 2. Mixtures containing cyclic dimethylsiloxanes

A continuous-dilatometer is described for the measurement of excess volumes of binary liquid mixtures. Emphasis of design is directed towards ease of operation coupled with a precision of ±0.002 cm 3 mol −1. Excess volumes have been measured for benzene + cyclohexane at 298.2 K and the results are compared with previous determinations. Excess volumes of six binary systems involving cyclic dimethylsiloxanes have been measured at one temperature. The experimental excess functions of several mixtures of pseudospherical molecules are compared with theoretical predictions based upon the van der Waals approximation. Poor agreement with experiment of the calculated excess volumes suggests the inadequacy of the Lorentz combining rule as applied to mixtures of molecules of this type.

Thermodynamics of solutions. Excess volumes of benzene, carbon tetrachloride, and mesitylene mixtures

The thermodynamic properties of a number of binary mixtures, differing from hard sphere nature, have been investigated (72) by utilizing a rigid sphere model first proposed by Longuet-Higgins and Widom (5). Values of excess Gibbs energy for equimolar mixtures are usually forced to agree with experimental values at one temperature to fix necessary parameters. In principle, the precise measurement of excess volume can provide a more direct and possibly more acceptable procedure for determining the fitting parameters involved in the hard sphere model considered. In addition, the excess volume is readily measured. From this point of view, the determination of the excess volumes for three binary mixtures was carried out. The results of the measurements for the systems benzene-mesitylene, benzene-carbon tetrachloride, and carbon tetrachloridemesitylene at 27 and 40°C are given along with a description of a simple method for the determination of excess volumes.

Excess volumes of some aromatic + cycloparaffin mixtures. Analysis of experimental errors in dilatometers using V-shaped cells

Potential sources of error in the direct measurement of excess volume in dilatometers using V-shaped cells were analyzed. Two corrections to the calculational procedure and several improvements in the apparatus and technique were defined. The excess volume of benzene + cyclohexane was measured at 298.15 K to confirm the accuracy of the experimental method by comparison with the results of other investigators for that standard system. Also, new experimental results were obtained for cyclopentane + benzene at 283.15, 298.15, and 313.15 K, for benzene + methylcyclohexane at 283.15, 313.15, and 343.15 K, and for toluene + methylcyclopentane at 298.15, 333.15, and 353.15 K.

Second virial coefficients of binary gas mixtures with complex formation

A modified apparatus was constructed for the measurement of excess volumes of binary gas mixtures according to the method of Edwards and Roseveare(1) allowing the measurement of the interaction parts of the second virial coeffients Bij with an error of ±3 per cent. The interaction coefficients Bij were measured for ethylene + ammonia, ethylene + methanol, and n-pentane + methanol and the Prausnitz association parameters were estimated. The plot of the quotient of association parameter and collision diameter against the enthalpy of formation of the AB complex is linear.

Thermodynamics of mixing: Excess volumes in polyisobutylene-solvent systems

Measurements of excess volumes of polyisobutylene in eight solvents are reported. The heats of mixing are examined with a view to rationalization.