Thin layer chromatography:
A six component mixture of compounds obtained by extracting plant leaves with an organic solvent was subjected to two-dimensional thin layer chromatography by placing a portion of the extract in one corner. First, it was developed with solvent A and after drying the plate and turning it to right angle, a different solvent was allowed to flow perpendicular to the direction of the first solvent. The black dot represents the start of original sample. Finally, the plate was sprayed with a reagent and the blue coloured spots were observed as shown in Figure.
Answer:
i) Cellulose filter paper used in PC should be free from any impurities and humidity and it should not be wet.
ii) No. van Deemter equation cannot be applied to TLC.
iii) Br2 cannot be used for the detection of organic compounds since it reacts along with the double bonds present in the compounds and it is also hazardous to handle.
iv) Rf and tr.values are different. By definition, tr = tM (1+k′) where k′ is the capacity factor representing column characteristics. However, Rf value is the ratio of distances travelled by the solute to that of the solvent.