JEE Main 2021 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 3 August 2021, Shift 2, Chemistry Q57

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

The inactivation process of virus is first order with respect to virus concentration and 2% of the virus was inactivated in the first one minute. Time taken (in minutes) for the virus to become 75% inactivated is

\underline{\hspace{2em}}

. (Nearest integer) [Use

\log_{10} 2 = 0.3010

\log_{10} 3 = 0.4771

]

Official answer

NTA final key.

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

Same idea in other shifts

Asked 5× 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 42 of the 174 JEE Main shifts held from 2017 to 2026.