JEE Main 2021ChemistryChemical KineticsEasyNumerical

JEE Main 2021 — Chemical Kinetics Question with Solution

JEE Main 2021 (25 Jul Shift 2)

Question

For a chemical reaction A→B, it was found that concentration of B is increased by 0.2 mol L-1 in 30 min. The average rate of the reaction is ________ ×10-1 mol L-1 h-1. (in nearest integer)

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Show full solutionCorrect answer: 4
Correct answer
4

Step-by-step explanation

A⟶B

t=0     0

t=30 min  0.2M

Av. rate of reaction =-Δ[A]Δt=Δ[B]Δt=(0.2-0)12

=0.4=4×10-1 mol/L×hr

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About this question

This is a previous-year question from JEE Main 2021, covering the Chemical Kinetics chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.