Experiment C: influence of the nature of the deposition solvent
On a porcelain well plate, deposit a spatula tip of solid ferrocene in 4 wells.
Dissolve the solid with:
- for well P1: dimethylformamide (DMF)
- for well P2: ethyl acetate
- for well P3: petroleum ether (EP) (add the solution from vial 11)
- for well P4: ethanol EtOH
Place these 4 solutions, using capillaries, on the same TLC plate, taking care to finally deposit the solutions from wells P3 and P4.
Immediately place the TLC plate to be eluted in a chamber containing petroleum ether (chamber C2). Leave to elute.
Calculate the corresponding Rf values and conclude.
It is found that ferrocene does not have exactly the same Rf depending on the initial solution in which it was dissolved: the Rf corresponding to the deposition in ethanol is slightly higher than that for the ferrocene solution in petroleum ether (PE) or hexane.
It is observed moreover that, in the case of DMF, the compound leaves streaks all along its elution.