Raoult’s law for ideal solution,
PTotal=PA+PB
PTotal=xA×PA∘+xB×PB∘
PTotal=21×400+21×600=500mmofHg
Dalton’s law,
yA×PTotal=PA
yA=PTotalxA×PA0=21×500400=0.4
yB=1−0.4=0.6
JEE Main 2019 — Chemistry Physical Chemistry
The vapour pressures of pure liquids A and Bare 400 and 600mmHg respectively at 298K.On mixing the two liquids, the sum of their volumes is equal to the volume of the final mixture. The mole fraction of liquid B is 0.5 in the mixture. The vapour pressure of the final solution, the mole fractions of components A and B in the vapour phase, respectively are
Held on 8 Apr 2019 · Verified 6 Jul 2026.
500mmHg,0.5,0.5
450mmHg,0.4,0.6
450mmHg,0.5,0.5
500mmHg,0.4,0.6
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