SC-740
Chromatography
Lower Sec Science · Secondary 1 · Hard · Chromatography
A student wants to separate a mixture of coloured food dyes using paper chromatography. After the solvent has moved up the paper, the spots are very faint and hard to see. What should the student do to make the spots visible, based on how chromatography is usually carried out?
- Spray the dried paper with a locating agent that reacts with the dyes to form coloured spots.
- Dip the paper back into the original dye mixture to darken the spots.
- Heat the wet paper strongly over a Bunsen burner until it turns brown.
- Add more solvent directly onto each spot after the run has finished.
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