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JEE Main 2021 — Chemical Kinetics Question with Solution

JEE Main 2021 (17 Mar Shift 1)

Question

For a certain first order reaction 32% of the reactant is left after 570 s. The rate constant of this reaction is ×10-3 s-1. (Round off to the Nearest Integer).

[Given: log10 2=0.301, ln10=2.303]

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Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

For 1st  order reaction,

K=2.303t·logA0At=2.303570sec·log10032

=1.999×10-3sec-1≈2×10-3sec-1

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About this question

This is a previous-year question from JEE Main 2021, covering the Chemical Kinetics chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.