A piston–cylinder assembly contains components 1 and 2 in vapor–liquid equilibrium. Assume ideal solution and ideal gas behavior. The composition of species 1 in the liquid is x1 = 0.50 and in the vapor is y1 = 0.25. Your technician performs an experiment where she adds a weight to the piston and compresses the system at constant temperature. Two phases remain at the fi nal pressure.
She claims that when she measures the mole fractions, both liquid and vapor decrease. Is this possible? Explain.