AApplication of the Congruence Principle to Viscosities of 1-Chloroalkane Binary Mixtures

1971 ◽  
Vol 49 (16) ◽  
pp. 2631-2635 ◽  
Author(s):  
B. M. Coursey ◽  
E. L. Heric
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Chain Length ◽  
Kinematic Viscosity ◽  
Binary Systems ◽  
Excess Gibbs Free Energy ◽  
Average Chain Length ◽  
Free Energy Of Activation ◽  
Congruence Principle ◽  
Chain Lengths

Viscosities are reported at 25 °C in five 1-chloroalkane binary systems. Mixture data are presented both as kinematic viscosity and as excess Gibbs free energy of activation for flow. The latter quantity is correlated with the average chain length in the mixtures by graphical and analytical forms of Brønsted and Koefoed's principle of congruence. This correlation serves as a basis for prediction of mixture viscosities for 1-chloroalkane pairs having chain lengths within the observed extremes: 1-chlorobutane and 1-chlorooctadecane. Errors as kinematic viscosity by this method are less than 5.5% for the systems studied.

Thermodynamic Excess Functions of Binary Liquid Mixtures with Chain Association of One Component*. Part I: The Excess Gibbs Free Energy GE/RT

1976 ◽  
Vol 31 (12) ◽  
pp. 1651-1660 ◽  
Author(s):  
F. Becker ◽  
M. Kiefer ◽  
P. Rhensius ◽  
H. D. Schäfer
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Chain Length ◽  
Liquid Mixtures ◽  
Binary Liquid Mixtures ◽  
Excess Gibbs Free Energy ◽  
Component Part ◽  
Excess Functions ◽  
Binary Liquid ◽  
Self Association

Abstract In this paper equilibrium models for the calculation of the excess Gibbs free energy of binary liquid mixtures are developed, the component A of which undergoes chain-forming self-association whilst the component B acts as an 'inert' solvent. It is shown that the extension of the well-known chain-association model of Mecke and Kempter, in which the probability of chain prolongation is assumed to be independent of chain length, is unable to establish satisfactory results because it does not exhibit sufficient unsymmetry. Reduction of the probability of chain growth with in-creasing chain length leads to an improved model with the geometric series replaced by the exponential series. This model, in which only two parameters are used, i. e. the equilibrium constants K for mutual solvation of A and B, and ρ for self-association of A, allows fitting of isothermal experimental GE /R T literature data on cycloalkanol-cycloalkane, alkanol-alkane, and NMF -CCl4 systems within the limits of experimental error. Compared with the two-parameter Wilson equation which gives equally small standard deviations, our equilibrium model has the advantage of allowing passage from GE to HE data and of being applicable to liquid-liquid equilibria.

scholarly journals Molar Interactions of Some Aromatic Hydrocarbons in n-Heptane by Viscometric Measurements at 298.15K

2018 ◽  
Vol 40 (1) ◽  
pp. 97-110
Author(s):  
Md Kamrul Hossain ◽  
M Abdur Rahaman ◽  
Shamim Akhtar
Keyword(s):  
Free Energy ◽  
Aromatic Hydrocarbons ◽  
Binary Systems ◽  
Composition Range ◽  
The Other ◽  
Excess Gibbs Free Energy ◽  
Geometric Fitting ◽  
Free Energy Of Activation ◽  
Three Body ◽  
Kister Equation

The viscosities, η , of pure n-heptane, toluene, o-xylene, mesitylene, and some of their binary mixtures covering the whole composition range have been measured at 298.15K. Deviations in viscosity, ∆η , was calculated using experimental results. The concentration dependencies of η were correlated to polynomial expressions, whereas, ∆η were fitted to the Redlich–Kister equation. Moreover, the values of the excess Gibbs free energy of activation, ∆G#E, of these mixtures were determined. Viscosity measurements of the binary systems were correlated with Grunberg and Nissan the three-body and four-body McAllister expressions. In all systems, ∆η were found to be negative in the whole range of composition with a single lobe having minimum at 0.6 mple fraction of aromatic hydrocarbon. While dispersive forces are suggested to dominate in n-heptane + toluene, for the other two systems  ‘favourable geometric fitting’ overpowers them due to the increasing number of  – CH3 groups in the relevant aromatic hydrocarbons. The Chittagong Univ. J. Sci. 40 : 97-110, 2018

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