Development time:

The development time will depend on the complexity of the mixture of solutes being separated, solvent system and the quality of paper and the ambient temperature. The diffusion of the solvent and the resulting separation into spots is termed as development of the chromatogram. It is necessary which paper should be equilibrated along with the solvent vapours in the chamber. For better resolution, reasonable R_f   values must be in the range of 0.4 to 0.8 with classical separation time being 1 to 2 hours. Following are the main sources of error:

• Lateral diffusion of the solutes.
• Variation in the structure of paper.
• These become significant especially for the concentrated solutes.
• Variation in the geometry of the assembly for the standard and unknown samples. However, this error can be easily eliminated by using the same tank for the two samples where similar experimental conditions are maintained.