Question
Two different food colourings, X and Y, are tested using chromatography.
Three pure dyes, 1, 2 and 3, are also tested.
The chromatogram is shown.
Which statements are correct?
1 X and Y both contain two or more dyes.
2 Dyes 2 and 3 are present in both X and Y.
3 The Rf of dye 1 is 0.625.
A 1 and 2 only B 1 and 3 only C 1, 2 and 3 D 2 and 3 only
Answer/Explanation
Ans: C
Question
Which statement about paper chromatography is correct?
A A solvent is needed to dissolve the paper.
B Paper chromatography separates mixtures of solvents.
C The solvent should cover the baseline.
D The baseline should be drawn in pencil.
Answer/Explanation
Ans: D
Question
The measurements from a chromatography experiment using substance F are shown. The diagram is not drawn to scale.
What is the \(R_{f}\) value of F?
A. 0.55 B. 0.61 C. 0.90 D. 1.64
Answer/Explanation
Ans:
B
Question
Chromatography is used to separate and identify the components in both coloured and colourless mixtures.
For colourless mixtures the chromatogram has to be treated with another chemical.
What is the name of this type of chemical?
A colouring agent
B display agent
C finding agent
D locating agent
Answer/Explanation
Ans: D