Get Answers to all your Questions

header-bg qa

Vapour pressure of pure benzene is 119 torr and that of toluene is 37.0 torr at the same temperature. Mole fraction of toluene in vapour phase which is in equilibrium with a solution of benzene and toluene having a mole fraction of toluene 0.50, will be :

Option: 1

0.137


Option: 2

0.237


Option: 3

0.435


Option: 4

0.205


Answers (1)

\\ \text{The partial pressure of toluene in the vapour phase is} \\ P_{T}=P_{T}^{0} X_{T}=37 \ torr \ \times \ 0.5=18.5 \ torr. \\ \\ \text{The partial pressure of benzene in the vapour phase is } \\ P_{B}=P_{B}^{0} X_{B}=119 \ torr \ \times \ 0.5=59.5 \ torr \\ \\ \text{The total pressure is } P_{T}+P_{B}=18.5 \ torr+59.5 torr \ =78 torr. \\ \text{The mole fraction of toluene in the vapour phase is } Y_{T}. \\ \text{It is given by the expression } Y_{T}= P_{T}/\text{total pressure} =18.5/78=0.237 \\ \text{Hence, the mole fraction of toluene in the vapour phase is } 0.237

Posted by

Kshitij

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE