Benzene systems, molar volumes

Figure 5.3 shows V and V2 for the (benzene + cyclohexane) system as a function of mole fraction, obtained in this manner.3 Shown on the graph are Fm, i and F, 2, the partial molar volumes (which are the molar volumes) of the pure benzene and pure cyclohexane. The opposite ends of the curves gives Vf and Vf, the partial molar volumes in an infinitely dilute solution. We note that... 

The dilution shift A i defined as the difference between the chemical shift of aromatic protons in the pure liquid and that in an infinitely dilute solution in nonpolar solvents, is inversely proportional to the molar volume (Vm) of the solute and directly proportional to the difference in the magnetic susceptibilities parallel and perpendicular to the axis of the ring.las, 134 On this basis Khetrapal and co-workers have argued134 135 that the percentage aromaticity (A) of a system relative to benzene (100%) can be calculated from the expression ... 

Figure 2. Molar volumes of hydrogeur-benzene systems ( ), data of Connolly (10). (----------------), Calculated [K12 = 0.17].

To apply this method, the Uquid molar volumes of the mixture and of the pure components need to be known. At a given pressure and temperature these values can be calculated from the equation of state. However, since sji according to Eq. (63) is volume-dependent, this involves an iterative procedure similar to that described by Danner and High [4] for the method of Chen et al. [50]. Eigure 2.12 shows the experimental solvent activity of the system poly(propylene oxide)-benzene at 347.85 K compared to the correlation by UNIQUAC and predictions by the GC-Flory model. The result of the correlation is almost perfect. The predicted solvent activities by the GC-Elory model are also very cJose to the experimental values. In Figure 2.13 a comparison is shown of experimental solvent activity... 

Mato, M. M. Balseiro, J. Saigado, J. Jimenez, E. Legido, J. L. Pineiro, M. M. Paz Andrade, M. I. Study on excess molar enthalpies and excess molar volumes of the binary systems 1,2-dichlorobenzene + (benzene, hexane, 1-chlorohexane) and 1,3-dichlorobenzene -t (benzene, hexane, 1-chlorohexane) at 298.15 K/. Chem. Eng. Data 2002,47,4-7... 

Eq. 13.14.1 is applicable to systems where the activity coefficients of the two components are symmetrical. It can thus correlate successfully only systems similar in structure and molar volumes, such as benzene-cyclohexane. 

The Fick diffusion coefficients for the system acetone(l)-benzene(2)-methanol(3) in the volume average reference velocity frame are given in Table 3.2. Calculate the elements of [D] in the molar average reference velocity frame. 

Figure 6-19. Dependence of the volume fraction 03 of the precipitant on the logarithm of the volume fraction 02 of the solute at the point of incipient turbidity for polystyrenes of different viscosity-average molar masses in a benzene-isopropanol system at 25 C (after A. Stasko and H.-G. Elias).

Singh, J. Pnug,H.D Benson, G. C. Molar excess enthalpies and volumes of benzene - isomeric xylene systems at 25.deg. J. Phys. Chem. 1968, 72,1939-1944... 

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