JEE Main 2008ChemistrySolutionsRelative Lowering Of Vapour Pressure And Roults LaweasyMCQ

JEE Main 2008 — Solutions Question with Solution

From: AIEEE 2008

Question

At 80oC, the vapour pressure of pure liquid ‘A’ is 520 mm Hg and that of pure liquid ‘B’ is 1000 mm Hg. If a mixture solution of ‘A’ and ‘B’ boils at 80oC and 1 atm pressure, the amount of ‘A’ in the mixture is (1 atm = 760 mm Hg)

Choose an option

Show full solutionCorrect option: D
Correct answer
D50 mol percent

Step-by-step explanation

At atmospheric pressure the boiling point of mixture is

At boiling point the vapour pressure of mixture,

atmosphere

Using the relation,

we get







or

or

or

or mol. percent

i.e., The correct answer is

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About this question

This is a previous-year question from JEE Main 2008, covering the Solutions chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.