JEE Main 2022 · ChemistryNumerical answerNumerical valueHardMulti-step

JEE Main 26 June 2022, Shift 1, Chemistry Q84

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

A flask is filled with equal moles of A and B. The half lives of A and B are 100 s and 50 s respectively and are independent of the initial concentration. The time required for the concentration of A to be four times that of B is __________s. (Given : ln 2=0.693)

Official answer

200

NTA final key.

Chapter: Chemical Kinetics
Topic: Integrated Rate Equations
Idea tested: First Order Half-Life

Same idea in other shifts

Asked 6× 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.