Part A.1 and Part B.3.
a. Why is it important to keep the developing chamber covered with plastic wrap during the development of the chromatogram?
b. The developing chamber is not covered with plastic wrap during the development of the chromatogram. Will the Dion value for the cation be greater than or less than the actual value as a result of this technique error? Explain.
2. Part A.4. Explain how the appearance of the chromatogram might change if the chromatographic paper were initially wet with water or had come in contact with the skin.
3. Part A.4. Why was a pencil used to mark the chromatogram and not a ballpoint or ink pen?
4. Part B.1. Explain why the cation samples are repeatedly spotted and dried on the chromatographic paper.
5. Part B.3. The eluent is to be below the 1.5-cm line on the chromatographic paper. Describe the expected observation if the eluent were above the 1.5-cm line.
6. Part C.2. Explain why the center of the band is used to calculate the Rf value for a cation rather than the leading edge of the band.
7. Suppose two cations have the same Rf value. How might you resolve their presence in a mixture using paper chromatography?