Clark Atlanta University SRING 2012 ORGANIC CHEMISTRY LAB I – CCHE 231L LAB PROCEDURE FOR MICROSCALE FLASH COLUMN CHROMATOGRAPHY This lab involves separating a solid mixture into its non-polar and polar components using column chromatography. Pre-lab Questions 1. Draw the structure of ferrocene and acetylferrocene. Determine which one is polar and non- polar. Explain in detail. 2. What function(s) does silica gel serve in column chromatography? 3. Under what conditions would column chromatography be use instead of Thin Layered Chromatography? Packing the Silica Gel Chromatography Column Obtain a Pasteur pipette and plug it with a small amount of cotton. Tamp it down lightly into the bottom of the column (Figure 1). Take care that you do not use either too much cotton or pack it too tightly. You just need enough to prevent the adsorbent from leaking out. Figure 1. Using a 10 mL beaker gently add a layer of dry silica to the Pasteur pipette until it is just below the indent in the pipette (Figure 2 and 4) . Tap the pipette to pack the silica level the top of the silica gel and to gently dislodge any trapped air bubbles (Figure 3). 1 | Page