Liquids A and B form ideal solution for all compositions of A and B at 25 ∘ C . Two such solutions with 0 . 25 and 0 . 50 mole fractions of A have the total vapor pressures of 0 . 3 and 0 . 4 bar, respectively. What is the vapor pressure of pure liquid B in bar?
A. A
P Total  = P A o X A + P B o X B ( i )   0 .3 = ( P A o ) 1 4 + ( P B o ) 3 4 P A ∘ + P B ∘ = 1 . 2 ( ii )   0 .4 = ( P A o ) 1 2 + ( P B o ) 1 2 P A ∘ + P B ∘ = 0 . 8 From equation (1) and equation (2) P B o = 0 .2   bar and P A o = 0 .6   bar
Related: Chemistry — Solutions · All PYQ Banks