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Saturday, 31 October

JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 29 June 2022, Shift 2, Chemistry Q81

Question 81 of 90 in this shift, Chemistry question 21 of 30, Section B.

A box contains 0.90 g of liquid water in equilibrium with water vapour at 27°C. The equilibrium vapour pressure of water at 27°C is 32.0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be ____ litre. [nearest integer] (Given: R = 0.082 L atm K−1\mathrm{K^{-1}} mol−1\mathrm{mol^{-1}}) (Ignore the volume of the liquid water and assume water vapours behave as an ideal gas.)

Official answer

29

NTA final key.

Chapter
States of Matter
Topic
Ideal Gas Laws
Idea tested
Ideal Gas Equation

Same idea in other shifts

Asked 10× 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.