Separation of analytes
Separation of analytes - contextAnalyte mixtures and separation - 1Analyte mixtures and separation - 2Analyte mixtures and separation - 3Introduction to chromatographyChromatographic columnsPrinciple setup of a chromatographic unitExample of separationChromatographic system - 1Chromatographic system - 2Standard gas chromatograph(Old) liquid chromatography unit(New) liquid chromatography unitHPLC columnsComparison GC and HPLC
SelftestProblems
1) GC-columns Answer 2) Which peak corresponds to 1,2,4-TCB? Answer 3) Peak area 100 times larger Answer 4) Unlabeled GC columns Help Answer 5) Which animation is correct? Answer 6) Concept map Hint
End of chapter5) Which animation is correct?
Problem:
Take a look at the following animations on the principle of chromatography (or more generally, transport of a retained compound through a porous system):
Can you see how the second animation deviates from the first?
Which animation is correctly visualizing the principle of chromatography?
Animation 1:
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Animation 1:
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Answer:
There are several instances in the second animation where all the molecules of one of the compounds are either in the mobile or in the stationary phase. What would the outflow concentration curve (i.e., the peaks) look like if this was correct?
In reality, the fraction of molecules that resides in the mobile or stationary phase at any time is always the same although the molecules themselves are constantly exchanged between both phases. This is accurately represented in the first animation.
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