Qualitative understanding of partition preferences
Introduction
Cavity modelRules for partitioningThe cavity model in quantitative terms
Selftest
1) What does the cavity model say? Answer 2) Main interactions ... ? Answer 3) Size of a solute molecule ... ? Answer 4) Size of the solvent molecule ... ? Answer 5) Interpretation of data Answer 6) "Like dissolves like" Answer 7) Concept maps 8) Functional groups Answer 9) Illustration by given data? Answer 10) Evaluation of the software PcKocWIN 11) H-bonds between given substances? 12) Tendency to distribute Answer 13) Gas chromatography Answer 
14) Henry's Law constant Answer 15) QuizProblems
Intermolecular interactions in every day life
FAQ12) Tendency to distribute
Question: Rank the four compounds (I − IV) indicated below in the order of increasing tendency to distribute from (a) air into hexadecane (mimicking an apolar environment), (b) from air to olive oil, and (c) from air to water.
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Answer:
The order of experimental data does not always match the results of qualitative estimates. However, differences in K-values are usually smaller than a factor 3. You cannot expect a qualitative estimation to perform better than that. In addition, please note that a qualitative estimation cannot always be carried out.
air −> hexadecane |
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The large difference between the partitioning coefficients of benzene and phenol are somewhat unexpected since they have a similar molecular size.
| air −> olive oil |
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| air −> water |
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