Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Which of the following statements about the composition of the vapour over an ideal 1 : 1 molar mixture of benzene and toluene is correct? Assume that the temperature is constant at 25oC . (Given vapour pressure data at 25oC , benzene = 12.8 kPa, toluene = 3.85 kPa)
ChemistrySolutionsNEETNEET 2016 (Phase 1)
Options:
  • A The vapour will contain a higher percentage of benzene.
  • B The vapour will contain a higher percentage of toluene.
  • C The vapour will contain equal amounts of benzene and toluene.
  • D Not enough information is given to make a prediction.
Solution:
2319 Upvotes Verified Answer
The correct answer is: The vapour will contain a higher percentage of benzene.
A - benzene, B - Toluene

PT=PAo XA+PBo XB

=12.8×0.5+3.85×0.5

=6.2+1.925

=8.125

Also, mole fraction of benzene in vapour form

YA=PAo XAPT=6.28.121=0.75

And mole fraction of Toluene in vapour form

YB=1-0.75=0.25

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.