Question

Consider 15 mL of an aqueous solution containing 2.0 g of an organic solute. If the distribution coefficient for the solute between ether and water is 20, calculate the percent of the compound that can be recovered with a single extraction with 13.9 mL of ether.

Answer 1

Let X = g extracted with ether, then
2 - X = g remaining in water.
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K_o/a = 20 = (X/13.9)/[(2-x)/15]
Solve for X, then
(X/2)*100 = % recovered in organic phase. I estimated very quickly to be about 45% but that's just a quickie. Check my work.

Answer 2

26