Biology / Unit 3 Bio 0498 short lesson, about 20 seconds
Activation Energy
Captions available
The idea
Activation energy is the input every reaction needs to reach its unstable transition state, even one that releases energy.
In practice
Sugar sits stably in a bowl because breaking it down, though exergonic overall, needs an activation-energy push it rarely gets at room temperature.
Where people slip
Activation energy is not part of a reaction's net free-energy change — it is recovered once the transition state resolves.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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