Experiment 6: Column Chromatography
October 14, 2016
Dr. Coleman Experiment 6: Column Chromatography
Today’s experiment is Column Chromatography. This experiment is used for separating mixtures with impurities. The unknown mixture is comprised of acetylferrocene and ferrocene. Some of the mixture will be saved for Thin layer Chromatography. Petroleum ether will be the solvent for pushing and separating the unknown mixture from each other. Alumina is a solid which will be packed into the column as a catalyst for separating the unknown mixture. When both liquids are collected from test tubes, they are used as samples on thin layer chromatography to determine their polarities. Pure acetylferrocene, pure ferrocene, and a mixture of Acetylferrocene …show more content…
Three components of column chromatography include a stationary phase, mobile phase, and solvent. Each phase is distinct to each other, but together run as one system in chromatography.
These components operate in fashion of a step ladder. The stationary phase is packed with material with no dissolution to liquids. For today’s lab, Alumina is the solvent of choice for running the stationary phase. Alumina is placed in the column to prevent solids from entering or exiting the column. The liquid phase is adding liquids in the column, provided their polarity doesn’t mix with the solvent. Liquids will force exit out of the column and stored in a beaker. Polar and nonpolar materials are pushed from the columns as each liquids are separated, thus retaining purity. Test tubes collect these liquids for polarity determination on thin layer …show more content…
We take the three liquids extracted from the column and spot them on chromatography paper by using capillary tubes. Then I put the spotted papers in the jar of 30:1 toluene/absolute ethanol solvent mixture and closed the lid. We waited 15 minutes for capillary action to separate liquids on paper. I pull out the papers from the jar and we measured the distance of each spot. Both the unknown sample and Acetylferrocene had covered half the distance of the paper. Ferrocene’s distance covered the near end of the paper. Ferrocene was the less polar of the three liquids on