An ideal solution of 2 mol chlorobenzene and 3 mol bromobenzene is enclosed in a cylinder - piston arrangement, and the piston is pulled outwards very slowly allowing equilibrium to be maintained at a

Question

An ideal solution of 2 mol chlorobenzene and 3 mol bromobenzene is enclosed in a cylinder - piston arrangement, and the piston is pulled outwards very slowly allowing equilibrium to be maintained at all times. The vapour pressure of pure chlorobenzene and pure bromobenzene are 300 tor and 200 torr respectively. If the vapour phase mole fraction of chlorobenzene is $Y_{1}$ in the first traces of vapours formed, and $Y_{2}$ when the last traces of liquid is about to be vapourized, what is $\frac{4 Y _{1}}{Y _{2}}$ ? (Assume the process to be isothermal).

Answer:

5.00

Solution:

I vapor:

$Y_{C_{2}} = \frac{X _{c} P _{c}^{\circ}}{X _{c} P _{c}^{\circ} + X _{b} P _{b}^{\circ}} = \frac{\frac{2}{5} \times 300}{\frac{2}{5} \times 300 + \frac{3}{5} \times 200} = 0.5$

Last Bubble:

$Y_{C_{2}} \frac{Y _{C_{1}}}{Y _{C_{2}}} = \frac{2}{5} = 0.4 = \frac{0.5}{0.4} = 1.25$

TestHub · Accepted Answer

I vapor: Y C 2 ​ ​ = X c ​ P c ∘ ​ + X b ​ P b ∘ ​ X c ​ P c ∘ ​ ​ = 5 2 ​ × 300 + 5 3 ​ × 200 5 2 ​ × 300 ​ = 0.5 Last Bubble: Y C 2 ​ ​ Y C 2 ​ ​ Y C 1 ​ ​ ​ ​ = 5 2 ​ = 0.4 = 0.4 0.5 ​ = 1.25 ​

Chemistry - Liquid Solution Question with Solution | TestHub

Doubts & Discussion