JEE Main 2022 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 27 July 2022, Shift 2, Chemistry Q84

Question 84 of 90 in this shift, Chemistry question 24 of 30, Section B.

When a certain amount of solid A is dissolved in 100 g of water at 25°C to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is 23.76 mmHg. The number of moles of solute A added is __________. (Nearest Integer)

Official answer

NTA final key.

Chapter: Solutions
Topic: Colligative Properties
Idea tested: RLVP to Molality Approximation Formula

Same topic in other shifts

All Colligative Properties questions

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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.