Dependence upon temperature of the excess molar volumes of tetrahydropyran + n-alkane mixtures

1995 ◽  
Vol 73 (3) ◽  
pp. 375-379 ◽  
Author(s):  
R. Bravo ◽  
M. Pintos ◽  
A. Amigo

Excess molar volumes VE, at 288.15 and 308.15 K and normal atmospheric pressure, are reported for the binary mixtures tetrahydropyran + n-alkanes (C7–C9). From the results, the differential coefficient (∂VE/∂T)p was estimated over the entire range of mole fractions. The Prigogine–Flory–Patterson theory and its applicability in predicting VE is tested. Keywords: Excess molar volumes, digital densimeter, tetrahydropyran, n-heptane, n-octane, n-nonane, Prigogine–Flory–Patterson theory.


1995 ◽  
Vol 73 (1) ◽  
pp. 139-145 ◽  
Author(s):  
José M. Pico ◽  
Consolaciôn P. Menaut ◽  
Eulogio Jiménez ◽  
José L. Legido ◽  
Josefa Fernàndez ◽  
...  

Excess molar volumes υE at 298.15 and 308.15 K and normal atmospheric pressure for the binary mixtures 2-pentanone + 1-chloroalkane (from 1-chlorobutane to 1-chlorooctane) were obtained from measurements of the density with an Anton Paar densimeter. The υE values for all mixtures were positive, and increase as the 1-chloroalkane length increases. Excess molar volumes depend slightly on the temperature. The same characteristics were found previously for the excess molar enthalpies of the same mixtures. Experimental υE values are compared with theoretical results using the Prigogine–Flory–Patterson model. Keywords: thermodynamics, liquid mixtures, excess volumes, ketones, chloroalkanes.



2002 ◽  
Vol 80 (5) ◽  
pp. 467-475 ◽  
Author(s):  
Amalendu Pal ◽  
Rakesh Kumar Bhardwaj

Excess molar volumes (VmE) and dynamic viscosities (η) have been measured as a function of composition for binary liquid mixtures of propylamine with 2,5-dioxahexane, 2,5,8-trioxanonane, 2,5,8,11-tetraoxadodecane, 3,6,9-trioxaundecane, and 5,8,11-trioxapentadecane at 298.15 K. The excess volumes are positive over the entire range of composition for the systems propylamine + 2,5-dioxahexane, and + 3,6,9-trioxaundecane, negative for the systems propylamine + 2,5,8,11-tetraoxadodecane, and + 5,8,11-trioxapentadecane, and change sign from positive to negative for the remaining system propylamine + 2,5,8-trioxanonane. From the experimental data, deviations in the viscosity (Δln η) and excess energies of activation for viscous flow (ΔG*E) have been derived. These values are positive for all mixtures with the exception of propylamine + 2,5-dioxahexane.Key words : excess volume, viscosity, binary mixtures.



2017 ◽  
Vol 232 (1) ◽  
Author(s):  
Wei Song ◽  
Hai Zhang ◽  
Zhenyu Yang ◽  
Juan Wang ◽  
Zishuang Yue ◽  
...  

AbstractIn this work, the experimental densities and viscosities have been determined for (propylene carbonate+acetonitrile, or dimethyl carbonate, or diethyl carbonate) binary mixtures over the whole concentration range at temperatures (293.15–333.15 K) and the atmospheric pressure. Excess molar volumes (



1998 ◽  
Vol 76 (12) ◽  
pp. 1860-1866
Author(s):  
Mohamed M El-Banna ◽  
Mervette M El-Batouti

Excess molar volumes, VE, for three binary liquid mixtures of cyclohexane + n-dodecane, n-tetradecane, and n-hexadecane were determined from density measurements at seven different temperatures in the range from 283.15 to 313.15 K and atmospheric pressure, over the entire range of mole fractions. The VE values were derived and the results show a regular negative pattern of behaviour for each of the three sets of the binary system. For cyclohexane, the magnitude of VE increases with the alkane chain length. The Prigogine-Flory-Patterson theory was applied to analyze the experimental behaviour by calculating three different contributions to VE, i.e., interactional, free volume, and internal pressure. The theory gives a representation of the main feature of the systems studied by using a fitted parameter to describe the behaviour throughout the composition range.Key words: excess molar volumes, binary mixtures, cyclohexane, n-dodecane, n-tetradecane, n-hexadecane, Prigogine-Flory-Patterson theory.



1985 ◽  
Vol 38 (10) ◽  
pp. 1435 ◽  
Author(s):  
J Ortega ◽  
MI Paz-Andrade ◽  
E Rodriguez-Nunez ◽  
L Romani

Excess molar volumes VEm at 298.15 K and atmospheric pressure were calculated over the entire composition range from densities measured with a vibrating-tube digital densimeter for the binary mixtures butyl acetate + methanol, + ethanol, + propan-1-ol, + butan-1-ol, + pentan-1- ol, + hexan-1-ol, + heptan-1-ol, + octan-1-ol, + nonan-1-ol and + decan-1-ol. The excess volumes are positive over the entire composition range for these mixtures except the system butyl acetate + methanol, for which all VEm values are negative. The excess volumes show a consistent trend towards more positive values as the length of the hydrocarbon chain of the alkanol increases. The results suggest the presence of specific interactions.



2000 ◽  
Vol 78 (4) ◽  
pp. 444-448
Author(s):  
Amalendu Pal ◽  
Gurcharan Dass

Excess molar volumes (VEm) and viscosities (η) for mixtures of triethylene glycol dimethyl ether + dichloromethane, + trichloromethane, and + tetrachloromethane have been determined at 298.15 K and atmospheric pressure over the whole concentration range. From the experimental results, deviations in viscosities (Δ ln η) have been calculated. These properties were fitted to the polynomial relations to obtain the coefficients and the standard deviations. The results have been analysed in terms of molecular interactions between components.Key words: experiments, data, excess volume, viscosity deviation, binary mixtures.



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