Chromatography (2014 VCE)

1) Four straight chain alkanols, S, T, U, V, with a general formula ROH, were analysed using a gas chromatograph combined with a mass spectrometer. The following chromatogram was produced.

What is the order of the alkanols from the highest molar mass to the lowest molar mass?
A. V, U, T, S
B. T, U, S, V
C. V, S, U, T
D. S, T, U, V

Solution

2) A thin layer chromatography (TLC) plate was set up with a non-polar solvent, hexane, and a polar stationary phase, silica gel. The chromatogram below was obtained. A ruler was then placed next to the plate.

The Rf value for the compound would be
A. 0.80
B. 0.78
C. 0.64
D. 0.61

Solution