Solutions Question 320
Question: The vapour pressure of pure benzene and toluene at a particular temperature are 100 mm and 50 mm respectively. Then the mole fraction of benzene in vapour phase in contact with equimolar solution of benzene and toluene is
Options:
A) 0.67
B) 0.75
C) 0.33
D) 0.50
Show Answer
Answer:
Correct Answer: A
Solution:
Total vapour pressure = vapour pressure of pure benzene + vapour pressure of $ =100+50=150mm $ We know, $ P_{C_6H_6}^{{}^\circ }=P\times X_{C_6H_6} $
$ 100=150\times X_{C_6H_6} $
$ X_{C6H6}=\frac{100}{150}=0.67 $
