JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 22 July 2021, Shift 2, Chemistry Q57

Question 57 of 90 in this shift, Chemistry question 27 of 30, Section B.

\mathrm{N_2O_{5(g)} \rightarrow 2NO_{2(g)} + \frac{1}{2} O_{2(g)}}

In the above first order reaction the initial concentration of

\mathrm{N_2O_5}

2.40\times10^{-2}

mol L

^{-1}

at 318 K. The concentration of

\mathrm{N_2O_5}

after 1 hour was

1.60\times10^{-2}

mol L

^{-1}

. The rate constant of the reaction at 318 K is ________

\times10^{-3}

min

^{-1}

. (Nearest integer) [Given : log 3=0.477, log 5=0.699]

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.