Pupil sheet · Paper chromatography
Paper chromatography — return questions
Name ______________________ Date ____________
Use one to two weeks after the lessons. Keep the notes and the lesson closed.
1. Explain
Keep the earlier explanation closed. Describe how to set up and finish paper chromatography. Explain why you use a pencil baseline, keep spots above the reservoir and mark the wet front immediately.
Prepare the paper and solvent, with reasons
Develop and finish in order
Explain the key precautions
2. Explain
Without the earlier diagram, explain how known samples help identify an unknown. Then explain why one visible spot doesn't guarantee purity.
3. Explain
At a later lesson, write the Rf equation from memory. State the origin of both measurements and whether Rf has a unit. Then explain when and why you use a locating agent.