Question

The suggested procedure for spotting a sample on a thin‑layer chromatography (TLC) plate involves transferring a droplet of concentrated solution from a capillary onto the plate, allowing it to dry, then repeating the process over the existing spot. Why is it advised to spot multiple times? to facilitate visualization by having a higher compound concentration to prevent the solvent in the developing chamber from evaporating to fill the capillary almost instantly by capillary action to achieve a high concentration of sample in a large spot

Answer 1

Correct is: to facilitate visualization by having a higher compound concentration

Step-by-step explanation:

It is advised to spot multiple times to have a higher compound concentration (more compound in a small spot). If the spot is too big, the compound will disperse and run unevenly.