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Raoult's Law and Vapor-Liquid Equilibrium: Example Problems

Try to solve these problems before watching the solutions in the screencasts.

Example Problem 1
Calculate the bubble temperature at 85 kPa for a binary liquid with x1 = 0.40. The liquid solution is ideal. The saturation pressures are (\(T\) in °C): \[P_1^{sat} \, = exp(14.3\,-\,\frac{2945}{T\,+\,224}) \;\;\; \;\;\;\;P_2^{sat} \, = exp(14.2\,-\,\frac{2943}{T\,+\,209}) \]
Example Problem 2

A fixed volume tank contains 1.0 mol of component A (PAsat = 2.0 bar) at a pressure of 1.9 bar. When 1.0 mol of liquid component B (PBsat = 1.0 bar) is added to the tank, and the system goes to equilibrium at the same temperature, the final pressure is 1.44 bar. Assume ideal gas and ideal solution for liquid phase. Determine the phase or phases present and their compositions and number of moles.