Thin Layer Chromatography Lab Report

Thin Layer Chromatography (TLC) is a technique of chromatography where compounds are separated from a mixture using an absorbent material on a structural sheet or plate. There are many uses for TLC, one use of this experiment is to answer how many components are in a mixture. When the TLC plate is placed in a mixture, the material on the plate absorbs the mixture in the beaker. The compounds spotted on the plate move along with the solvent via capillary action. The farther the spots move up the TLC plate the less polar the molecule is. The quantity of components in a mixture can be determined by the Rf values on the TLC plate. If two compounds are plated on the same TLC plate and develop with the same Rf values then they are most likely the …show more content…
At the start of a reaction only the reactants will show up on the TLC plate. However, as the reaction takes place, the product spots start becoming visible. The product spots become more intense as the reaction progresses. Simultaneously, the reactant spots become less visible because less reactant is left within the solution. As the reaction reaches 100%, the reactant spots no longer show and the product spots are the only visible spots. A third use for TLC is to identify if it is a mixture or just one substance. For this, it is necessary to develop a TLC plate with an unknown sample. After developing, if there are multiple spots on the plate, then the sample is a mixture. Conversely, if there is only one spot after being developed then it is safe to assume that it is a single compound. The Rf value, also known as the Retardation Factor, is a ratio of the distance traveled by a substance divided by the distance traveled by the solvent. Every TLC plate is different. This is why measuring the distance from the origin to the center of the point for a substance is not applicable. The substance being tested travels at a fixed ratio to the solvent at any condition. Therefore, this is how the Rf value becomes

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Lab Report Thin Layer Chromatography