JEE Main 2020ChemistrySolutionsRelative Lowering Of Vapour Pressure And Roults LawmediumMCQ

JEE Main 2020Solutions Question with Solution

From: JEE Main 2020 (Online) 7th January Morning Slot

Question

At 35oC, the vapour pressure of CS2 is 512 mm. Hg and that of acetone is 344 mm Hg. A solution of CS2 in acetone has a total vapour pressure of 600 mm Hg. The false statement amongst the following is :

Choose an option

Show full solutionCorrect option: B
Correct answer
Ba mixture of 100 ml. CS2 and 100 ml. acetone has a volume < 200 ml.

Step-by-step explanation

As the vapour pressure of mixture increases so the force of attraction of mixture is less than the individual component.

Since the vapour pressure of the solution is greater than individual vapour pressure of both pure components, the solution shows a positive deviation from Raoult’s law.

SolH 0

As SolH 0 then solution is endothermic.

and here Sol Volume 0. As Sol Volume 0 then a mixture of 100 ml. CS2 and 100 ml. acetone has a volume more than 200 ml. It happens because the distance between molecules increases due to force of attraction of mixture decreases.

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About this question

This is a previous-year question from JEE Main 2020, 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.