The rate of First order reaction is 0.04 mol L$^{-1}$ s$^{-1}$ at 10 minutes and 0.03 mol L$^{-1}$ s$^{-1}$ at 20 minutes after initiation. Half life of the reaction is ________ minutes. (Given log2 = 0.3010, log3 = 0.4771)

JEE Main 2024 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 30 January 2024, Shift 1, Chemistry Q87

Question 87 of 90 in this shift, Chemistry question 27 of 30, Section B.

The rate of First order reaction is 0.04 mol L

^{-1}

^{-1}

at 10 minutes and 0.03 mol L

^{-1}

^{-1}

at 20 minutes after initiation. Half life of the reaction is ________ minutes. (Given log2 = 0.3010, log3 = 0.4771)

Official answer

NTA final key.

Chapter: Chemical Kinetics
Topic: Integrated Rate Equations
Idea tested: First Order Integrated Rate Law

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Asked 13× 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.