What three things should be checked on the TLC plate before carrying out the separation on a column?
We need at least 10 more requests to produce the answer.
0 / 10 have requested this problem solution
The more requests, the faster the answer.
What three things should be checked on the TLC plate before carrying out the separation on...
6. Why is it necessary to perform a thin layer chromatography (TLC) before carrying out the Column chromatography? (0.75 points)
8.5 TLC is commonly employed with column chromatography to monitor the separation of colorless compounds. The column is allowed to elute into many containers, usually test tubes. This is followed by a TLC on a long plate containing the same stationary phase as the column chromatography. Since a large number of tubes must be spotted, by spotting only every other (or every three etc.) tube on the plate. After visualization (by UV), the TLC plate is used to judge which...
For the column chromatography experiment - After separation, analyze your results by TLC. Draw the TLC plate results below (actual size). Calculate Rf for each spot. Label identity of each spot.
2. What are the phases involved in TLC? 3. What is coated on the TLC plate? 4. What is the purpose of lining the wall of the TLC chamber with paper? 5. Why is it important to use a small amount of the mobile phase? 6. Why should you remove the TLC plate before the mobile phase reaches the top? 7. What type of compounds are visible with UV light? 8. With a polar stationary phase and non-polar mobile phase,...
Sometimes elution of a TLC plate with one solvent does not achieve a good separation. How could you elute the same TLC plate with two different solvents?
1. Why should any marks on the TLC y marks on the TLC plate be done in pencil and not pen? 2. A spot on a TLC plat migrates 4.2 cm as the solvent plates my migrates 4.2 cm as the solvent plates migrates 8.0 cm up the plate. What is the Rivalue for this spot? Show your calculati
3. If the TLC plate development had stopped before the solvent front reached the top of the TLC plate (i.e. maybe it reached the middle of the TLC plate when it was stopped, instead): a) Would the Rf values have been affected? If so, how? If not, why not? Give a numerical example to support your answer. b) Would the size of the spots have been affected? If so, how? If not, why not? (Hint: think about the diffusion of...
For TLC plate separation, why do we use Rf values instead of distance measurements (e.g. the spot travelled 5 cm from the starting line)? What would happen if we compared solvent systems using distances rather than Rf values?
10. Consider the separation of the mixture of the compounds shown below using TLC analysis using silica gel plates. (2pts each) oso ooo a OH a) What would be a reasonable eluent that could be used to separate all three components on the TLC plate? Explain your reasoning. b) List the order of elution when using your proposed eluent. Explain your reasoning using complete sentences. c) What will be the effect on separation if you increase the polarity of your...
Explain what happens during the separation process when two molecules pass through a column or up a TLC plate.