Question

1. A students performed a TLC experiment on a mixture containing two compounds. However, he observed only one spot after visualizing the TLC plate with U.V. light. Give a possible explanation for the student observing only one spot.

2. TLC plates could be made of different particle size of silica. If one used a smaller particle size of silica in the TLC plate, how would that effect the results of a TLC experiment? Explain your answer.

Answer 1

this observation indicates the nature of two compounds on TLC

one compound is appeared under UV light tells the it has the extended conjugation and UV active molecule

such as aromatic compounds

in case of other substance not not showing on TLC under UV light tells it is a aliphatic compound does not have any extended conjugation (such as aliphatic amines, alcohols, etc)

to see these molecules on TLC we have to use some stains such as KMnO4, 2,4 DNP, Hansen reagent for polyhydroxy compounds