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Sarkari MCQs Government Exam Question Bank
Question no. 7707

A chemical reaction takes place when reactant molecule energy ________________ the reaction activation energy?

Select your answer for: A chemical reaction takes place when reactant molecule energy ________________ the reaction activation energy?
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Answer: D. Equal to or more than

Explanation

Molecules must possess sufficient kinetic energy during collisions to surmount the potential energy barrier. Activation energy represents the minimum energy threshold required for successful bond rearrangement. Particles with energy equal to or greater than this threshold successfully form reaction products. Maxwell-Boltzmann distributions describe the fraction of molecules possessing specific kinetic energies at given temperatures. Increasing system temperature shifts the molecular energy distribution toward higher kinetic energy levels. Unsuccessful collisions occur when reactant kinetic energy falls below the required activation threshold.

Industrial reactors are heated to ensure reactant molecules meet the necessary activation energy criteria. Combustion engines rely on spark ignition to provide localized energy exceeding the activation threshold. Understanding energy requirements helps chemical engineers optimize reactor operating temperatures safely. Energy levels strictly less than activation energy result in elastic collisions without chemical change. Requiring strictly more than activation energy ignores molecules possessing energy exactly equal to the threshold. Option D correctly encompasses both exact threshold and higher energy reactant molecules.

Subject
Engineering
Category
Chemical Engineering
Topic
—
Difficulty
medium

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