Separation of analytes

Separation of analytes - context
Analyte mixtures and separation - 1
Analyte mixtures and separation - 2
Analyte mixtures and separation - 3
Introduction to chromatography
Chromatographic columns
Principle setup of a chromatographic unit
Example of separation
Chromatographic system - 1
Chromatographic system - 2
Standard gas chromatograph
(Old) liquid chromatography unit
(New) liquid chromatography unit
HPLC columns
Comparison GC and HPLC
Selftest
Problems
     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 chapter

4) Unlabeled GC columns

 

Problem:

You are working in a laboratory. In a drawer, you find 2 old GC columns that have no labels. In order to find out the characteristics of the stationary phase, you inject standards of the following substances on both columns: o-xylene, benzaldehyde, and phenol. At 100°C (isotherm), you obtain the following retention times:

Substanz Column 1
Retention time (sec)		 Column 2
Retention time (sec)
o-Xylene 145 100
Benzaldehyde 170 320
Phenol 97 2900

 

4a) Based on these findings, what can you say about the properties of the columns?

4b) You need to separate benzene from the three substances o-xylene, benzaldehyde, and phenol. Based on the above findings, would you expect that it is possible with one of the above columns? If yes, which one?

4c) You need to separate anisole from the three substances o-xylene, benzaldehyde, and phenol. Based on the above findings, would you expect that it is possible with one of the above columns? If yes, which one?