chemsample-infraredspectroscopy-tlc-discussion


 * Discussion**

1. a) hexane, toluene, dichloromethane, ethyl acetate, methanol

b) The more polar an eluent, the larger Rf value is found per compound.

c) In the toluene that we chose, generally the more polar a compound, the smaller the Rf value. In our particular experiment, the benzhydrol, which is less polar and the benzophenone, had a larger Rf value due to the hydrogen bonds interacting with the silica in the TLC plate.

2. We chose toluene because it is slightly polar and allowed for a better separation of the compounds than a more polar eulent like the methanol.

3. a) This could cause tailing, making it hard to determine an Rf value.

b) This could cause the solution being tested to dissolve into the eluent, causing the resulting spots to be inaccurate.

c) This could cause the spots of compounds to continue moving off the TLC plate, and making it impossible to calculate an Rf value.

d) This could cause the compounds to not have properly separated, again making it impossible to determine Rf values for each individual compound.

e) This would make the chamber devoid of the eluent and therefore not allowing the TLC plate to develop properly.

4. You could use the TLC plate at various points during the reduction process to see when the spots on the TLC have reached the Rf values specified for each compound.

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