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Problem:
The value of K (@25oC) for compound A when partitioned between water and cycloheptane is 3.37. Starting with a solution of 848 g of compound A in 497 mL of water what quantity of compound A (in grams) would remain in the water layer after two successive extractions with cycloheptane each using 331 mL of cycloheptane.

Solution:

The issue can be easily solved using two simple steps:

1. We should find the recovery factor for two successive extractions:


2. Finding the mass of compound A that remains in water:


Answer:
80.1 g of compound A would remain in the water.



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