JEE Main 2022 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 29 July 2022, Shift 2, Chemistry Q85

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

Assuming 1µg of trace radioactive element X with a half life of 30 years is absorbed by a growing tree. The amount of X remaining in the tree after 100 years is ____

\times\ 10^{-1}\ \mu

g. [Given: ln 10 = 2.303; log 2 = 0.30]

Official answer

NTA final key.

Chapter: Chemical Kinetics
Topic: Integrated Rate Equations
Idea tested: Concentration After N Half-Lives

Same topic in other shifts

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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.