A Better Way to Separate Mixtures

Progress of a liquid-liquid extraction using two identical extractions of a sample (initial phase) with fresh portions of the extracting phase. All numbers are fractions of solute in the phases A = analyte, I = interferent. 

A liquid-liquid extraction in which solutes are extracted back and forth between fresh portions of two extracting phases. 

In chromatography, the extracting phase that moves through the system. 

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