Unit 12 · Experimental Techniques and Chemical Analysis

Question Bank

Cambridge IGCSE Chemistry 0620 · 59 questions

Q45Experimental Techniques and Chemical Analysis

Why is the baseline in paper chromatography drawn in pencil, not ink?

(a)Pencil is easier to see

(b)Pencil (graphite) does not dissolve in the solvent and move up the paper

(c)Ink would make the Rf value larger

(d)Pencil absorbs the solvent faster

Correct answer: (b) Pencil (graphite) does not dissolve in the solvent and move up the paper

Explanation: Ink is a mixture of dyes that would dissolve and run, adding extra spots; graphite is insoluble.

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