Question

Name:_ Post-Lab Questions You're the TA in an organic lab and the students are running a column to separate the following compounds: methyl cinnamon trans-cinnamic acid HW 1. Student A calls you over and explains that after running his column and showing you the TLC of fractions 1-5 which only have one spot by UV. He combined these fractions, removed the solvent and took a melting point. He is worried something is wrong because he got 38°C and not 133°C. How would you advise him? HW 2. Student B calls you over and explains that after running her column on a mixture of two compounds and collecting 25 fractions, the first compound has come off the column completely (eluted). She's got to run to class and needs to collect the second compound. What would you advise her to do to expedite the collection of the second spot? Explain your reasoning. HW 3. List at least two concepts from the lecture that are foundational to understanding the column chromatography lab.

Answer 1

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