Quantitative prediction of K values

Introduction

Fragment models
sp-LFERs
pp-LFERs
Comparison of the various methods
Predictive models based on molecular structure

Critical remarks on approaches from chemical engineeringh

Selftest
Problems
     Problem 1
     Problem 2
     Problem 3
           Answer
     Problem 4
           Answer
     Problem 5
           Answer
     Problem 6
           Answer
     Problem 7
     Problem 8
     Problem 9

Problem 6

Develop one (or better) various models (i.e. equations), that facilitate the prediction of equilibrium partition constants of organic chemicals between air and Tenax at 100°C. As a basis you can use experimental partition coefficients for the following compounds: h-heptane, n-octane, n-decane, ethylbenzene, propylbenzene, butylbenzene, 2-butanone, 2-hexanone, 2-heptanone und 2-nonanone, ethyl acetate und di-ethylether (see Tenax.xls, reference: Schneider, M. and K.-U. Goss Anal. Chem. 2009, 81, 3017-3021.  Journal link Download pdf ).

Which physico-chemical properties of these chemicals do you need for setting up a model?

Which general form (equation) should the model have?

How do you proceed in order to get the concrete prediction model?

What can you say about the applicability range of your model?

Some of the calibration compounds listed above have boiling points below, others above 100°C. Does that matter for the calibration and applicability of the model? What about compounds that are solid at 100°C?

If you could measure 3 or for more experimental values for the partitioning to Tenax, which compounds would you choose and what improvement would this bring to your model?