Question

What is the formula for the theoretical extraction efficiency of a liquid-liquid extraction, in terms of the fraction of the analyte left in the original phase? If nobody has ever made you calculate this before, the Chemistry Libretexts page on liquid-liquid extractions will be helpful.

Answer 1

Answer:

$q_{aq}=\frac{V_{aq}}{KV_{org}+V_{aq}}$

Explanation:

Hello,

The requested formula is:

$q_{aq}=\frac{V_{aq}}{KV_{org}+V_{aq}}$

Whereas $q_{aq}$ is the cumulative fraction remaining after the extraction, $K$ the distribution coefficient and the $V$ the volume for the aqueous and organic phases

It is suitable when we assume that the analyte is originally at the aqueous phase and the aforesaid fraction stands for the efficiency as well (https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Book%3A_Analytical_Chemistry_2.0_(Harvey)/07%3A_Collecting_and_Preparing_Samples/7.7%3A_Liquid%E2%80%93Liquid_Extractions)

Best regards.