What would happen if the student did not stop the development before the solvent reached the top of the paper
What would happen if the student did not stop the development before the solvent reached the top of the paper.
The solvent would wash away the dye..
Why is it important to remove the chromatography paper from the beaker before the solvent front reaches the top of the paper
Why is it important to remove the chromatography paper from the beaker before the solvent front reaches the top of paper? Because you wouldn’t be able to measure the rf value unless you can measure the start to front of the solvent on the chromatography paper.
Why is the solvent front important
It is important to mark the solvent level on the chromatography paper when you remove it from the petri dish because when you change the orientation; the component absorbed may rise or fall depending on the orientation of the paper.
What information does the solvent front provide us with
-Solvent front = distance up a TLC plate that the developing solvent travels. –used in determining the Rf value. -TLC chamber = medium in which the TLC is performed. -Spotting solvent = solvent used to dissolve the compound to be analyzed.
What would be the consequences of immersing the initial spots in your filter paper with your developing solvent
If the spots were immersed they would dissolve in the solvent and be pulled down into the solvent itself. … The solvent rises up the paper by CAPILLARITY. The solvent flows through the paper, over and past the mixture of substances.
When should the chromatogram be removed from the beaker
– When the first solvent front reaches is about 1cm from the top of the chromatogram, all chromatograms are removed from their solvents. – When the first solvent front reaches is about 2cm from the top of the chromatogram, all chromatograms are removed from their solvents.
Why is it important the ink dots are not submerged in the solvent
It is important that the solvent level is below the line with the spots on it. … As the solvent slowly travels up the paper, the different components of the ink mixtures travel at different rates and the mixtures are separated into different colored spots.
What would happen if the solvent level is above the level of the spots
The level of the solvent system is too high. If the level of the solvent system in the chamber is above the spot when the plate is inserted, the compound from the spot will dissolve in the solvent instead of migrating up the plate. You may see irreproducible results if you reuse the solvent system for several TLCs.
What is meant by the solvent front
[′säl·vənt ‚frənt] (analytical chemistry) In paper chromatography, the wet moving edge of the solvent that progresses along the surface where the separation of the mixture is occurring.
Where should the solvent level be with respect to the dots
The solvent level has to be below the starting line of the TLC, otherwise the spots will dissolve away. The lower edge of the plate is then dipped in a solvent.
Which solvent system gave the best results
Which solvent system gave the best results? The 75% hexane and 25% ethyl acetate gave the best results.
How do you know if separated pigment spots
How could you find out whether the separated pigment spots you have observed on your chromatogram are single, pure pigments or a mixture of two or more? Use a different solvent and/or a different stationary phase, this means pigments which may have run together will separate out.
What factors are involved in the separation of the pigments
What factors are involved in the separation of the pigments? The solubility, size of particles, and their attractiveness to the paper are all involved in the separation.
Why is it important to mark the solvent front immediately
It’s important only if you want to determine retention/retardation factor absolutely for something you chromatographed. “Immediately” because it will soon vanish as the solvent evaporates. … Solvent front is the the furthest point reached by the solvent in chromatography.
Why must the solvent front be near the top of the paper
In thin layer or paper chromatography the origin should be above the solvent because it could otherwise wash the sample spot into the solvent trough. To allow the solvent to spread, until it forms concentric rings of pigments.
Can you still use your data if the mobile phase in the beaker covers the spot of dye you are trying to separate
can you still use your data if the mobile phase in the beaker covers the spot of dye you are trying to separate? What should you do if this happens? no. … which is less soluble in the mobile phase, a spot at the top of the chromatogram or at the bottom?
What would happen if your initial solvent level is above the baseline
Experiment 5: Thin Layer Chromatography and Melting Point 62 4) What would happen if your solvent level is above the level of the initial spots? Answer: The spots would dissolve into the reservoir of eluting solvent.
Why is it important to not let the solvent line travel past the end of the TLC plate
The baseline must be above the solvent level in the TLC chamber, so the solvent does not dilute to samples so much that they dissolve. … If the solvent line travels past the end of the TLC plate, then the Rf value will not be able to be measured and calculated. 4.
Why is it important that the chromatogram is stopped before the solvent front reaches the top what would happen to the pigment spots if the chromatogram was left running for a long time
When to stop the chromatogram – running the chromatogram for longer gives better separation of the pigments but it is critical to stop the chromatogram before solvent front reaches the cork/bung – further than this will prevent measurement of the solvent front, so Rf values cannot be calculated.
What happens if the solvent front reaches the top of the plate
However, if the solvent reaches the top of the plate, the chemicals continue to move up. This means that if left long enough, the chemicals will all merge together at the top of the plate, eliminating any separation that you could have seen on the plate.
What has happened to the size of the starting material spots Why
The size of the starting materials spots has decreased in size. This has happened as the material has moved up the TLC. How much time did it take to complete the reaction? It took about 34 mins for the reaction to complete.