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In a solution the mole fraction of the solute is 0.1. At 298 K the solution's molarity equals its molality, and its density is 2.0 g/cm³. Find the ratio of the molecular weights of solute to solvent (MW_solute / MW_solvent).
- 9
- 10
- 18
- 0.1
Correct answer: 9
Solution
Equating molarity and molality with density 2.0 gives MW_solute = 9*MW_solvent, so the ratio is 9.
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