A stoppered flask at 25 C contains 250 mL water, 200 mL octanol, and 50 mL of air. An unknown mass of o-xylene is added to the flask and allowed to partition among the phases. After equilibrium has been established, 5.0 mg of o-xylene are measured in the water.
What is the total mass (g) of o-xylene present in the flask?
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