Liquid Mixtures Involving Cyclic Molecules:  Xenon + Cyclopropane

Abstract

The total vapor pressure of liquid mixtures of xenon and cyclopropane has been measured at 161.39 K (the triple-point of xenon) and at 182.33 K (the triple-point of dinitrogen oxide), as a function of composition. At 182.33 K the liquid densities were also measured. The mixtures show positive deviations from Raoult's law. Both the excess molar Gibbs energy ( ) and the excess molar volume ( ) were calculated from the experimental data. For the equimolar mixture, = 90.6 J mol-1 at 161.39 K, = 124.1 J mol-1 at 182.33 K, and = −0.758 cm3 mol-1 at 182.33 K. The excess molar enthalpy ( ) could be estimated from the temperature dependence of and found to be −168 J mol-1. The results were interpreted using the 1cLJ perturbation theory of Fisher et al.

On the behaviour of solutions of xenon in liquid cycloalkanes: Solubility of xenon in cyclopentane

“…As previously mentioned, we have found that mixtures of xenon containing a cyclic component (i.e., xenon + cyclopropane [4] and xenon + cyclobutane [5]) exhibit large positive deviations from Raoult's Law (and consequently larger values of G E ), but more negative excess volumes and enthalpies than those containing a linear analogue (xenon + propane [6] and xenon + butane [7]). …”

“…RT dp (4) where V ∞ 2 is the partial molar volume of the solute at infinite dilution and p sat 1 is the vapour pressure of the pure solvent. The vapour pressure of cyclopentane was taken from Ref.…”

“…With that in mind, we have undertaken a number of studies with the purpose of assessing the effect of the molecular shape on the thermodynamic behaviour of liquid mixtures, in particular those involving cyclic molecules [2,3]. From the experimental point of view, binary mixtures such as xenon + cyclopropane [4] and xenon + cyclobutane [5] have been investigated and the results compared with those of mixtures containing the linear analogues xenon + propane [6] and xenon + butane [7]. In general, we have found that mixtures containing a cyclic component exhibit larger positive deviations from Raoult's Law (and consequently larger values of G E ), but more negative excess volumes and enthalpies than those containing a linear analogue.…”

“…This effect was also used to explain the results exhibited by mixtures involving cyclopentane [9,10], whose plate-like anisotropic molecular structure would favour the condensation of n-alkanes on its surface. Since cyclopropane and cyclobutane are also plate-like anisotropic rotors, it was suggested that a "condensation" type phenomenon could arise between these molecules and xenon, a particle with a high polarizability, which enhances the dispersion forces [4,5].…”

Liquid mixtures involving triangular molecules: (vapour + liquid) equilibria of (xenon + trimethylboron)

“…trichloride BCl , is a planar molecule with a considerable quadrupole. 3 Trimethylboron has, in addition, some interesting features which make the study Ž . of systems involving this molecule worthwhile.…”