Relation between distribution ratio and percent extraction:

The percent extraction is a more useful term for reporting the analytical data. Figure shows the interconversion of D and % E at a unit volume ratio. It can be seen from the plot that when the extraction efficiency approaches 100%, the distribution ratio approaches infinity as a limit. For the extractions to be in the range of 99 - 100% the distribution ratio will vary from 99 to infinity. Such a large difference in the distribution ratio is 99 and infinity may be misleading when in reality the extraction would be nearly complete in both the cases.

Figure: Relation between distribution ratio and percent extraction