Question

Liquids A and B form an ideal solution in the entire composition range. At 350 K, the vapor pressure of pure A and pure B are 7 × 10³ Pa and 12 × 10³ Pa, respectively. The composition of the vapor in equilibrium with a solution containing 40 mole percent of A at this temperature is : 

(1) x_A = 0.76 ; x_B = 0.24 

(2) x_A = 0.37 ; x_B = 0.63 

(3) x_A = 0.28 ; x_B = 0.72 

(4) x_A = 0.4 ; x_B = 0.6

Answer 1

Correct option: (3) x_A = 0.28 ; x_B = 0.72

Explanation:

= 2.8/10 = 0.28

Y_A = composition of vapour phase.

Y_B = 0.72