Qualitative understanding of partition preferences

Introduction
Cavity model
Rules for partitioning
The cavity model in quantitative terms

Selftest
Problems
     1) Give a qualitative explanation
     2) Estimate the extraction efficiency
           Answer
     3) Assign partition constants to substances
           Answer
     4) Fuel accident
           Answer
     5) Mixture of similar isomeres ... ?
           Answer
     6) Extraction with pentane or diethyl ether?
     7) Prediction of partition constants
           Answer
     8) Assign data to substances
           Answer
     9) Explain saturated vapor pressure
     10) Apolar surface
Intermolecular interactions in every day life
FAQ

2) Estimate the extraction efficiency

Organic polymers are often used as absorption agents in the extraction of organic pollutants from water samples. You already have some experience with two of these absortion agents (see first lines of the table). you now would like to estimate, if extraction is sufficently high for the other substanzens listed in the table. Please provide a short explanation for your answer. In case the given information does not allow for an answer, please also explain why.

Pollutant

Organic polymer I

Organic polymer II

3-Methylhexane

extraction not sufficient

extraction sufficient

Cyclohexane

extraction sufficient

extraction sufficient

Dibutylether

extraction not sufficient

extraction sufficient

a) Heptan

 

sufficient extraction,
just as with cyclohexan

extraction sufficient

b) Octanal

 

extraction not sufficient,
probably similar to dibuthylether

extraction sufficient

c) 1,4-Dichlorobenzene

 

extraction sufficient,
because it is apolar and larger in size than cyclohexane.

extraction sufficient

d) Hexanol

 

extraction not sufficient,
because it is smaller and therefore not as efficient as methylhexanol

extraction sufficient

e) Pentylamin

 

probably not sufficient,
because bipolar like methylhexanol and therefore smaller

bipolar, but smaller than methylhexanol, therefore unresolved

 

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