JEE Main 2020 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 4 September 2020, Shift 1, Chemistry Q48

Question 48 of 75 in this shift, Chemistry question 23 of 25.

If 75% of a first order reaction was completed in 90 minutes, 60% of the same reaction would be completed in approximately (in minutes) __________. (Take : log 2=0.30; log 2.5=0.40)

Official answer

60.00

NTA final key (Sep 2020).

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.