CAIE A Level Chemistry 9701 · Analytical techniques
A sample of a perfume is analysed by gas–liquid chromatography. The chromatogram shows four peaks. The peak areas are: P, 1.8 cm²; Q, 3.6 cm²; R, 0.6 cm²; S, 2.4 cm². The retention times are: P, 1.2 min; Q, 2.5 min; R, 4.1 min; S, 5.3 min.
Suggest, with reasons, which compound is present in the largest amount and which compound interacts most strongly with the stationary phase.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Suggest means: Apply what you know to an unfamiliar situation. There may be more than one acceptable answer. Reason from the principle you have learned to the new context, and say which principle you are using.
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