JEE Main 2024 · ChemistryNumerical answerNumerical valueMediumCalculation

JEE Main 29 January 2024, Shift 1, Chemistry Q87

Question 87 of 90 in this shift, Chemistry question 27 of 30, Section B.

For a reaction taking place in three steps at same temperature, overall rate constant

K=\frac{K_1K_2}{K_3}

. If

Ea_1

Ea_2

and

Ea_3

are 40, 50 and 60 kJ/mol respectively, the overall Ea is ________ kJ/mol.

Official answer

NTA final key.

Chapter: Chemical Kinetics
Topic: Arrhenius Equation
Idea tested: Effective Activation Energy for Complex Reactions

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