How does the liquid rise through the filter paper?
How does the liquid rise through the filter paper?
How does the liquid rise through the filter paper ? Answer. By means of capillary action….
Why is a pencil needed for the TLC experiment?
Do not use excessive forces when writing on a TLC plate as this will remove the stationary phase. It is important to use a pencil rather than a pen because inks commonly travel up the plate with the solvent….
Why can’t you use a pen on a TLC plate?
You can’t use a pen because the ink will travel up the TLC plate with the TLC solvent, just like your chemical samples do. You can only spot/label/mark TLC plates using a pencil. The graphite in a pencil will not run up the plate!
What happens if the spot line and positions are marked on the plate with a ballpoint pen when preparing a TLC plate for development?
What happens if the spot line and positions are marked on the plate with a ballpoint pen when preparing a TLC plate for development? Ballpoint pen ink consists of organic compounds that will move with the development solvent and cause additional spots to appear on the plate.
What happens if the spots are made too small?
2What happens if the spots are made too small when preparing a TLC plate for development? -If the spots are made too small when preparing a TLC plate for development, it will be very difficult to observe the results or there will be no spots at the end of the process.
What happens if the spots are added below the level of the solvent when preparing a TLC plate for development?
Developing a Plate The solvent level has to be below the starting line of the TLC, otherwise the spots will dissolve away….
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….
Why must the spots be above the solvent level?
It is important to keep the dye spots above the solvent level because if the spot is not below the solvent level, the molecules will not dissolve into the solvent and, then, would not be able to separate D.
What will 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. You observe a melting point for this same compound isolated in your experiment as 177–181°C.
Why must you be careful not to touch the filter paper with your fingers?
Ungloved human hands are made of proteins, which are made of amino acids. We are careful not to touch the filter paper so that we do not contaminate it with our own amino acids, which would later show up in the chromatography and throw off our data.