Final answer:
Colorless substances in thin layer chromatography can be seen by using derivatization to react with a reagent that produces a colored product. Staining can be used to create a permanent record of the observations.
Step-by-step explanation:
In thin layer chromatography, colorless substances can be seen through the use of a technique called derivatization. Derivatization involves turning the colorless substances into a colored form by reacting them with a specific reagent. This reaction produces a colored product that can be visualized in thin layer chromatography.
For example, if a colorless compound reacts with a reagent that forms a colored complex, the resulting product can be seen on the chromatogram as a separate spot or band. This allows for the identification and analysis of colorless substances in a mixture.
To make a permanent record of the observations in thin layer chromatography, you can use a technique called staining. Staining involves treating the chromatogram with a dye or stain that selectively binds to the substances of interest, making them visible. The stained chromatogram can then be photographed or stored as a permanent record of the observations.