Assume an organic compound has a partition coefficient between water and diethyl ether equal to 7.33. If there are initially 9.81 grams of the compound dissolved in 100.0 mL of water, how many grams will remain in the aqueous layer after extraction with one 30.0 mL portion of ether?

Answer 1

This link is helpful:
http://chemistry.csudh.edu/faculty/noel/CHE317L/Extraction%20Experiment.htm

read up to X = 8.0 grams of A extracted into the ether.

For your question, you would subtract x from 9.81g after you solve for x.