Why is UV light used in TLC?
Why is UV light used in TLC?
Ultraviolet light is often the first visualization technique attempted on an eluted TLC plate because it is nondestructive and rather simple to carry out. If a dark spot is seen with a UV lamp, it is customary to circle the spot with pencil (as in Figure 2.46b), as the spot will be invisible when the lamp is removed.
What are the advantages and disadvantages of thin layer chromatography?
Advantages And Disadvantages Of Thin Layer Chromatography
- An easy method of separation of the components.
- In this technique, fewer types of equipment are used.
- All components of UV light is achievable to visualize.
- The non-volatile compounds can be separated by this method.
Why do we mark TLC plates with pencil and not with pen?
Why do you use a pencil and not a pen to mark TLC plates? Answer: The pen ink becomes mobile on the plate and travels up the TLC plate with TLC solvent. But the solid particles of graphite in the pencil won’t get dissolved and hence can be used to mark TLC plates.
What does higher RF value mean?
A high Rf (Ie 0.92) would refer to a substance that is very non-polar. Ie that substance moved a 92% of the entire distance the solvent traveled. A low Rf value (0.10) would refer to a substance that is very polar. IE that substance was only able to move 10% of the entire distance the solvent traveled. Term.
Can an RF number be greater than 1?
Is it possible to have an Rfnumber greater than 1? Why or why not? -In order to have an Rfvalue greater than 1 the pigment would have to move further than the solvent. Since the pigment is carried by the solvent an Rfgreater than one is not possible.
Why are anthocyanins not visible in chromatogram?
In this process, the mixed pigments are dissolved in a mixture of two (or more) solvents and allowed to soak into a piece of paper by capillary action. Anthocyanins are reddish, violet, or blue, and are not soluble in organic solvents, thus typically do not move up the chromatogram at all.