This Layer Chromatograph The objective of the lab was to reveal the active components in commercial analgesic preparations using thin layer chromatography. The thin layer chromatography separation method is a liquid mobile phase that carries the components of the mixture over a solid stationary phase. The stationary phase contains polar hydroxide groups on the surface of the silica gel. A component is separated from the mixture in the mobile solvent when it interacts with the immobile silica gel. The more polar the functional groups are in an organic compound, the easier it is for the silica gel the bind to it. Because the silica gel is porous, the solvent is able to move up the stationary phase through capillary action. This action causes the spotted mixture to move up the plate. Greater the separation up the silica gel, the higher the Rf value. The Rf is calculated by …show more content…
This was most likely the result of the functional groups within Advil not having as strong of polar interactions with the silica gel, which allowed the spot to stay in the solvent for a longer distance. This same observation holds true for Aspirin, Ibuprofen, and Naproxen Na. Because the Rf values were most similar to Advil, the standards Aspirin, Ibuprofen, and Naproxen Na were retested again for further comparison. The 75% ethyl acetate-25% hexane solvent was reused for the third plate because it gave the best separation between the components within the mixture. The spots were evenly spaced out across the TLC plate. The other solvents the two partners used had adequate separation; however, the 75% ethyl acetate-25% hexane solvent attained the best separation. A solvent that is too polar will cause the compounds to travel too much and not give a great separation. A non-polar solvent will cause the compounds to not travel far enough to give a good separation. The 3rd TLC plate results are as seen