Deuterium isotope effects on the partial molal volumes of cyclohexane, acetone, and acetonitrile in carbon tetrachloride

1983 ◽  
Vol 61 (12) ◽  
pp. 2684-2687 ◽  
Author(s):  
G. Ronald Brown ◽  
Julian K. Edward ◽  
John T. Edward

At 25 °C both molar volumes V and partial molal volumes [Formula: see text] in carbon tetrachloride of cyclohexane-d12 and of acetone-d6 are smaller than V and [Formula: see text] of the corresponding protio compounds. However, both V and [Formula: see text] of acetonitrile-d3 are larger than V and [Formula: see text] of acetonitrile-h3, and in solvent cyclohexane [Formula: see text] of acetone-d6 and of acetone-h6 are approximately equal. Apparently deuteration has not only a steric effect, but (in polar compounds) a counter-balancing effect, which may be polar.

1975 ◽  
Vol 53 (19) ◽  
pp. 2965-2970 ◽  
Author(s):  
John T. Edward ◽  
Patrick G. Farrell

The partial molal volumes [Formula: see text] of nonpolar organic molecules (i.e. those having more than three aliphatic carbon atoms per polar hydroxyl, ether, amine, amide, or urea group) in water at 25 °C are given by their van der Waals volumes υw plus the additional empty volume provided by an enclosing shell 0.53 Å thick. An equation relates [Formula: see text] to υw More polar compounds (i.e. those having fewer than two or three aliphatic carbon atoms per polar group) have [Formula: see text] smaller than calculated by the equation; the shrinkage in [Formula: see text] from that computed is linearly related to the fraction of the total surface area of the molecule occupied by the polar group.


1979 ◽  
Vol 57 (22) ◽  
pp. 2892-2894 ◽  
Author(s):  
John T. Edward ◽  
Patrick G. Farrell ◽  
Fereidoon Shahidi

The partial molal volumes [Formula: see text] or 47 mono- or polycyclic alkanes, ethers, alcohols, ketones, and bromides have been determined in carbon tetrachloride at 25 °C. [Formula: see text] of most of these compounds can be calculated with moderate (±1–2%) accuracy using an equation containing parameters previously developed for acyclic compounds, and an additional cyclization parameter C, which is roughly linear with the number n of atoms in the ring, from n = 3 (C = +5.3 mL mol−1) to n = 10 (C = −21.0 mL mol−1). Substituted cyclohexanols and some polyfunctional compounds had [Formula: see text] considerably lower than calculated.


1979 ◽  
Vol 44 (6) ◽  
pp. 950-953 ◽  
Author(s):  
Fereidoon Shahidi ◽  
Patrick G. Farrell ◽  
John T. Edward ◽  
Persephone Canonne

1983 ◽  
Vol 61 (7) ◽  
pp. 1414-1416 ◽  
Author(s):  
Fereidoon Shahidi

The partial molal volumes at infinite dilution [Formula: see text] for a number of halobenzenes are measured and related to their van der Waals volumes. Results indicate larger volume increments for halogen atoms in halobenzenes than those in alkyl halides. Possible explanations are forwarded. The effect of steric overcrowding in ortho-substituted benzenes on the [Formula: see text] values are evaluated.


1979 ◽  
Vol 57 (19) ◽  
pp. 2585-2592 ◽  
Author(s):  
John T. Edward ◽  
Patrick G. Farrell ◽  
Fereidoon Shahidi

The partial molal volumes [Formula: see text] in carbon tetrachloride at 25 °C of 13 ketones, 18 alcohols, and 17 mono- or poly-functional ethers, all acyclic, have been determined. Results are in reasonable agreement with [Formula: see text] calculated from an equation developed previously, using previous parameters plus the following: increments (in mL mol−1) of 8.72 for carbonyl, 6.1 for hydroxyl, 4.4 for oxygen in a monofunctional ether, and 5.8 for oxygen in a polyfunctional ether; decrements δ (in mL mol−1) of −1.68 for [Formula: see text] for [Formula: see text] for [Formula: see text] for [Formula: see text], and −1.93 for [Formula: see text]. The increments for carbonyl and hydroxyl are smaller than the van der Waals volumes of these groups, and indicate some degree of complexation to carbon tetrachloride. Only a roughly linear relation is found between [Formula: see text] of alcohols in water and [Formula: see text] in carbon tetrachloride, possibly because of the intrusion of additional effects such as structure-promotion in water.


1979 ◽  
Vol 57 (22) ◽  
pp. 2887-2891 ◽  
Author(s):  
John T. Edward ◽  
Patrick G. Farrell ◽  
Fereidoon Shahidi

The partial molal volumes of n-alkanes and n-alkanols dissolved in benzene, ethanol, or cyclohexane are given with satisfactory accuracy by the equation previously developed for solutions in carbon tetrachloride, if certain parameters (the covolume, the volume increment for the hydroxyl group, and the volume decrement for some gauche interactions) are changed. Additionally, it is necessary to postulate a greater coiling of the alkyl chains when dissolved in cyclohexane.


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