Factors:
It has been observed that Rf values are influenced by the impurities in the paper and solvent, temperature and saturation of the atmosphere. Following factors may be considered;
i) Presence of other ions e.g. presence of chloride is carried out with nitrate solutions.
ii) Acidity of the original solution-This may be needed to avoid hydrolysis and its need in the formation of soluble complex.
iii) Development time- Sometimes it rises along with the running time. Thus optimum time might be determined.
iv) Presence of other cations or anions as impurities.
v) Ambient temperature.
Because Rf value depends on the distribution of complex species of the cations along with different organic solvents, solvents should be carefully chosen.
The method of paper chromatography is primarily used for qualitative identification though it could also be used for quantitative determination but with a poor precision. Therefore, it could be at best considered as semi-quantitative technique.