At 23.0^°C, the vapor pressure of acetonitrile, CH₃CN, is 81.0 torr while that of acetone, C₃H₆O, is 184.5 torr. What is the vapor pressure of a solution that contains 0.550 moles of acetonitrile and 0.350 moles of acetone? (Assume the mixture behaves as an ideal solution.)

Question

Quizplus · Accepted Answer

The vapor pressure of the solution can be calculated using Raoult's Law: P_total = (X_acetonitrile * P_acetonitrile) + (X_acetone * P_acetone). The mole fractions are X_acetonitrile = 0.550 / (0.550 + 0.350) = 0.611 and X_acetone = 0.350 / (0.550 + 0.350) = 0.389. Therefore, P_total = (0.611 * 81.0) + (0.389 * 184.5) = 121 torr.

At 230°C, the Vapor Pressure of Acetonitrile, CH3CN, Is 81

At 230^°C, the Vapor Pressure of Acetonitrile, CH₃CN, Is 81