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Thin Layer Chromatography

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Thin Layer Chromatography
The main objective of this experiment was to use a Thin-layer chromatography analytic technique to analyze the relative polarity of given samples and to identify the components of a given unknown solution. TLC is usually done on a small plate coated with silica which is the stationary phase. The solvent is the mobile phase. Small sample of different compounds is placed across the plate and each plate is then put into a jar containing different solvents. Each solvent climbs up the plate with capillary action with different rate bringing up the sample to the top of the plate along with it. After the plate is allowed to dry, the relative distance the compounds traveled along the plate can be compared to that of the solvent using a ratio of Retention factor, Rf.
A sample of five compounds and one unknown was placed on a small TLC plate. The original spot of each compound was represented with alphabetical letter which is ~ 1cm from the bottom of the TLC plate. Accordingly, A represented the acetanilide solution, B represented the benzophenone solution, C represented the mandelic acid solution, D represented benzyl solution, E represented Benzoic acid and X represented the unknown. This process was repeated four times making the total of five TLC plates samples. Five empty jars were obtained and a peace of large filter paper was inserted into each jar sideways. Approximately 10ml of solvent was added into each jar. Each jar contained solvent with unique ethyl acetate-hexane proportion. Accordingly, jar 1 contained Solvent 1: 10% ethyl acetate – 90% hexanes, jar 2 contained Solvent 2: 25% ethyl acetate – 75% hexanes, jar 3 contained Solvent 3: 50% ethyl acetate – 50% hexanes , jar 4 contained Solvent 4: 75% ethyl acetate – 25% hexanes and jar 5 contained Solvent 5: 90% ethyl acetate – 10% hexanes.
Each TLC...

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