Understand that in an ideal mixture, the vapor in equilibrium with a liquid is always enriched in the more volatile component (the one with the higher vapor pressure) relative to the liquid — the basic principle behind distillation.
Bubble Pressure
550.0 mmHgVapor Mole Fraction, y1
0.727Raoult's law (bubble pressure): P = x1·P1sat + x2·P2satVapor composition: y1 = x1·P1sat / PSet liquid composition x1 to 1 (pure A). Confirm the bubble pressure equals P1sat exactly, and the vapor is 100% A.
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