Chromatography Vs Tlc

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According to Chemguide, Chromatography is a physical method that is used to separate a mixture of chemical substances into its components, which then can be closely analyzed. All forms of chromatography share this same principle. Here, a mobile phase travels through a stationary phase, carrying the components of the mixture with it. It is possible that the mobile phase and the stationary phase have similarities or differences that affect the overall interaction between each other and the analyte. Separation of the individual components is achieved because each component travels at different rates.
Likewise, Thin Layer Chromatography (TLC) is a chromatography technique where separation of the components in a mixture occurs on a sheet of glass,
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Also, it travels at a slower rate due to its tight interaction with the adsorbent. The reverse is the less polar a component of the mixture is, the less it is held by the adsorbent and the more distance it can travel up with the eluent. With that, it travels at a faster rate compared to the more polar components, as it is freer to move. Thus, the TLC plate will have several spots indicating the various components of the mixture. If most of the spotted mixture is overwhelmingly more polar than the eluent itself, than hardly any separation is achieved, as the spot of the mixture will be held tightly to the adsorbent. If the polarity of the eluent had been more polar than the spot of the mixture, then hardly any separation is achieved, as most of the spotted mixture will have moved up with the solvent and only one spot will be left. Generally, the eluent and the spotted mixture should be relatively close in polarity to allow optimal separation.
Moreover, other variables play a role in TLC and is essential in the way TLC operates. The setup of the TLC development chamber affects the accuracy and success of separation. The TLC plate is developed by first spotting the substance with a melting point capillary onto the baseline. Prior to this, a pencil is used to indicate where the spot of the mixture will be. It
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Ultimately, TLC helps to determine the identity of the components by the retention factor. According to Wikipedia, the retention factor ("R" _"f" ) is the distance traveled by the component over the distance traveled by the solvent. The "R" _"f" value indicates the polarity of the components, as it is directly proportional to the distance traveled by the component, which then indicates the polarity. The smaller the "R" _"f" value, the less distance traveled by the component, inferring a more polar substance. Ultimately, the "R" _"f" value of the various components can be used to determine their identities by matching it with known "R" _"f" values of compounds, or by inferring the relative position of

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