CAPE Chemistry Unit 2 · 2017 · Paper 1 · Question Q16

Item 16 refers to the following diagram which represents a paper chromatogram of food dyes obtained using water as the solvent. A spot of a sample was originally placed at Z. It contained the components X and Y. Which of the following statements regarding the components of X and Y is correct?

1. (A)X is more strongly adsorbed by the paper than Y, and X has a larger R_f value than Y.
2. (B)X is more strongly adsorbed by the paper than Y, and X has a smaller R_f value than Y.
3. (C)Y is more strongly adsorbed by the paper than X, and Y has a larger R_f value than X.
4. (D)Y is more strongly adsorbed by the paper than X, and Y has a smaller R_f value than X.

This question uses a figure or table from the paper — you'll see it when you practise.