JEE Main 2020 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 4 September 2020, Shift 1, Chemistry Q47

Question 47 of 75 in this shift, Chemistry question 22 of 25.

At 300 K, the vapour pressure of a solution containing 1 mole of n-hexane and 3 moles of n-heptane is 550 mm of Hg. At the same temperature, if one more mole of n-heptane is added to this solution, the vapour pressure of the solution increases by 10 mm of Hg. What is the vapour pressure in mm Hg of n-heptane in its pure state __________ ?

Official answer

600.00

NTA final key (Sep 2020).

Chapter: Solutions
Topic: Colligative Properties
Idea tested: Relative Lowering of VP

Same idea in other shifts

Asked 12× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.