The vapor pressure of pure acetone (propanone) is 266 torr. When a non-volatile solute is added, the vapor pressure of acetone above the solution falls to 232 torr. What is the mole fraction of the non-volatile solute in the solution?

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The mole fraction of the non-volatile solute in the solution can be calculated using Raoult's law, which states that the vapor pressure of a solvent above a solution (P_solution) is equal to the vapor pressure of the pure solvent (P_pure) multiplied by the mole fraction of the solvent (X_solvent). The decrease in vapor pressure is due to the presence of the non-volatile solute, so we can find the mole fraction of the solute by understanding the change in vapor pressure.Given:- Vapor pressure of pure acetone (P_pure) = 266 torr- Vapor pressure of acetone with non-volatile solute (P_solution) = 232 torrFirst, calculate the mole fraction of acetone (solvent) in the solution:$$X_{solvent} = \frac{P_{solution}}{P_{pure}} = \frac{232}{266} \approx 0.87$$Since the mole fraction of the solvent plus the mole fraction of the solute must equal 1 (because they make up the whole solution), we can find the mole fraction of the solute by subtracting the mole fraction of the solvent from 1:$$X_{solute} = 1 - X_{solvent} = 1 - 0.87 = 0.13$$Therefore, the mole fraction of the non-volatile solute in the solution is 0.13.

The Vapor Pressure of Pure Acetone (Propanone) Is 266 Torr