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JEE Main 27 July 2022, Shift 2, Chemistry Q85

Question 85 of 90 in this shift, Chemistry question 25 of 30, Section B.

[A]

\rightarrow

[B] Reactant Product If formation of compound [B] follows the first order of kinetics and after 70 minutes the concentration of [A] was found to be half of its initial concentration. Then the rate constant of the reaction is

x\times10^{-6}\ \mathrm{s^{-1}}

. The value of

x

is __________. (Nearest Integer)

Official answer

165

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.