Vapor Pressure Lowering The vapor pressure of a pure solvent is REDUCED when a nonvolatile solute is added. This is summarized by Raoult's Law: Psolution = Xsolvent Posolvent Where: Psolution is the vapor pressure of the solution Xsolvent is the mole fraction of the solvent in the solution = (mol solvent)/(mol solvent + mol solute) Pºsolvent is the vapor pressure of the pure solvent As more solute particles are added, the mole fraction of the solvent goes down, and the vapor pressure is reduced.

Vapor Pressure Lowering The vapor pressure of a pure solvent is REDUCED when a nonvolatile solute is added. This is summarized by Raoult's Law: Psolution = Xsolvent Posolvent Where: Psolution is the vapor pressure of the solution Xsolvent is the mole fraction of the solvent in the solution = (mol solvent)/(mol solvent + mol solute) Pºsolvent is the vapor pressure of the pure solvent As more solute particles are added, the mole fraction of the solvent goes down, and the vapor pressure is reduced.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter11: Properties Of Solutions

Section: Chapter Questions

Problem 7RQ: Vapor-pressure lowering is a colligative property, as are freezing-point depression and...

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