Activation energy
What Activation energy means in Chemistry GCSE, as defined for AQA.
Definitions of Activation energy
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Reference: AQA
The minimum amount of energy that particles must have to react, shown on a reaction profile as the vertical gap from the reactant energy level up to the peak of the curve.
The energy that collisions must have at least for a reaction to occur; raising temperature increases the proportion of collisions with energy greater than or equal to it.
The minimum amount of energy that particles must have to react, needed to break the bonds in the reactants and begin forming new bonds.
The minimum energy that colliding particles need to react; a collision with less energy does not lead to reaction.
An initial energy input a reaction can still need to start, which does not make it endothermic overall.
The minimum energy that particles must have when they collide for a reaction to occur.
Topics that use Activation energy
- Collision theory and activation energy (AQA GCSE)
- Factors which affect the rates of chemical reactions (AQA GCSE)
- Reaction profiles (AQA GCSE)
- The energy change of reactions (HT only) (AQA GCSE)
Related terms
- Catalyst
- Collision theory
- Exothermic
- Overall energy change
- Bond breaking
- Bond energies
- Bond making
- Collision frequency
Using Activation energy in the exam
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