JEE Main 2022 · ChemistryMultiple choiceSingle correctMediumCalculation

JEE Main 26 July 2022, Shift 2, Chemistry Q64

Question 64 of 90 in this shift, Chemistry question 4 of 30, Section A.

At 30°C, the half life for the decomposition of

\mathrm{AB_2}

is 200 s and is independent of the initial concentration of

\mathrm{AB_2}

. The time required for 80% of the

\mathrm{AB_2}

to decompose is Given: log 2 = 0.30 log 3 = 0.48

(1)200 s
(2)323 s
(3)467 sOfficial answer
(4)532 s

Official answer

Option 3

NTA final key.

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

Same idea in other shifts

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.