A sample of 19 mg of 9-fluorenone is dissolved in 5 mL of diethyl ether. The resulting organic solution is extracted with 10 mL of water. Assuming the Kp for 9-fluorenone in diethyl ether/
water is 9.5, how much 9-fluorenone would remain in the ether layer? SHOW YOUR WORK

15.70mg would remain

Explanation:

Partition coefficient is used to extract or purify a solute from a solvent selectively to avoid interference from other substances. For the problem, formula is:

Kp = Concentration 9-fluorenone in ether / Concentration of solute in H₂O

After the solute, 9-fluorenone, is extracted with water, the mass that remains in ether is:

(19mg - X)

Where X is the mass that now is in the aqueous phase

Replacing in Kp formula:

9.5 = (19mg - X) / 5mL / (X /10mL)

0.95X = 19mg - X / 5mL

4.75X = 19 - X

5.75X = 19

X = 19 / 5.75

X = 3.30mg

That means 9-fluorenone that remain in the ether layer is:

19mg - 3.30mg =

if you're asking what comes out, it's steam.