0654.C12.3.02 — Interpret simple chromatograms to identify: 3 State and use the equation for Rf: (a) . unknown substances by comparison with distance travel: past paper questions
Real questions on 0654.c12.3.02 — interpret simple chromatograms to identify: 3 state and use the equation for rf: (a) . unknown substances by comparison with distance travel
The newest 5 of 5 written questions. Open one to see it on the real paper.
- 0973/41 · May/June 2023 · Q2b(ii)[2]
Identify which of the dyes, A, B, C and D, are in the food colouring X.
See it on the paper → - 0973/41 · May/June 2021 · Q2b(i)[1]
State which mixture contains an insoluble food colouring.
See it on the paper → - 0973/41 · May/June 2021 · Q2b(ii)[2]
Explain which mixture is separated into the greatest number of soluble food colourings. Refer to Fig. 2.3 in your answer.
See it on the paper → - 0973/41 · October/November 2020 · Q2d[2]
Calculate the R f value of the spot from food colouring A. R f value =
See it on the paper → - 0973/42 · May/June 2019 · Q5b(ii)[2]
Fig. 5.3 shows the chromatogram he obtains. solvent front orange yellow dark green light green drawing not to scale Fig. 5.3 Table 5.1 lists the R f values of the coloured compounds on the chromatogram. Table 5.1 coloured compound R f carotene 0.91 chlorophyll A 0.42 chlorophyll B 0.16 xanthophyll 0.77 Use Table 5.1 to...
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What examiners said
Almost all candidates where able to correctly identify at least one of the dyes present in food colouring X. Correct identification of 1, 2 or 3 dyes were regularly seen. Very rarely was the incorrect answer of C seen.
— Examiner report, May/June 2023, 0973/41 Q2(b)(ii) (Cambridge)
The mixture with the insoluble food colouring was usually correctly identified.
— Examiner report, May/June 2021, 0973/41 Q2(b)(i) (Cambridge)
The mixture with the greatest number of soluble food colourings was usually correctly identified. Only the best answers explained why X had not been chosen or that Z had the greatest number of spots above the line.
— Examiner report, May/June 2021, 0973/41 Q2(b)(ii) (Cambridge)
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