activation energy


: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule

Examples of activation energy in a Sentence

Recent Examples on the Web Additionally, the material exhibits a low activation energy, indicating minimal energy barriers for lithium-ion movement. IEEE Spectrum, 15 Feb. 2024 This energy is called the activation energy. Svenja Lohner, Scientific American, 10 Nov. 2016 The firmness of beans, which was measured by use of a tenderometer, decreases during blanching according to a first order reaction with 40 kcal/mole activation energy. Ncbi Rofl, Discover Magazine, 26 Nov. 2010 What all of these examples have in common is that the former require less activation energy—the initial self-discipline and oomph to start something—and feel good immediately but crappy later on. Brad Stulberg, Outside Online, 24 May 2022 If the activation energy is too high, the reaction does not occur. Svenja Lohner, Scientific American, 10 Nov. 2016 Just about everything in my life—from getting out of bed to exercising to writing to coaching to reading—required a significant amount of activation energy. Brad Stulberg, Time, 20 Sep. 2021 The problem, of course, is that authoring statements requires little activation energy (often little more than a Slack message to a Black employee, asking for input), and no energy at all once the statement has been issued. C. Brandon Ogbunu, Wired, 25 May 2021 These create the activation energy required for a high explosive to react. Caroline Delbert, Popular Mechanics, 19 Feb. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'activation energy.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1924, in the meaning defined above

Time Traveler
The first known use of activation energy was in 1924

Dictionary Entries Near activation energy

Cite this Entry

“Activation energy.” Dictionary, Merriam-Webster, Accessed 25 Apr. 2024.

Kids Definition

activation energy

: the least amount of energy required to change a stable molecule into a reactive molecule

Medical Definition

activation energy

ac·​ti·​va·​tion energy ˌak-tə-ˈvā-shən- How to pronounce activation energy (audio)
: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule

called also energy of activation

More from Merriam-Webster on activation energy

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