The vapor pressure of water at 20°C is 17.5 mmHg. What is the vapor pressure of water over a solution prepared from 2.00 * 10² g of sucrose (C₁₂H₂₂O₁₁)and 3.50 * 10² g water? A)0.51 mmHg B)16.0 mmHg C)17.0 mmHg D)18.0 mmHg E)19.4 mmHg

Question

Quizplus · Accepted Answer

The vapor pressure of a solution is calculated using Raoult's Law: P_solution = X_solvent * P_pure solvent. First, calculate the moles of sucrose and water. Moles of sucrose = 200 g / 342.3 g/mol = 0.584 mol. Moles of water = 350 g / 18.015 g/mol = 19.42 mol. Mole fraction of water (X_water) = 19.42 / (19.42 + 0.584) = 0.971. Vapor pressure of the solution = 0.971 * 17.5 mmHg = 17.0 mmHg.

The Vapor Pressure of Water at 20°C Is 17