Collision theory
What Collision theory means in Chemistry GCSE, as defined for AQA.
Definitions of Collision theory
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Reference: AQA
For a reaction to happen, particles must collide with at least the activation energy, and the rate depends on the frequency and energy of collisions between particles.
The model used to explain why reaction rates change when conditions change, stating that particles must collide with sufficient energy for a reaction to occur.
Particles in a gas or solution move randomly and collide constantly, but only collisions with at least the activation energy produce a reaction.
The idea that more particles per unit volume lead to more frequent successful collisions, used to justify the hypothesis.
Chemical reactions can occur only when reacting particles collide with each other and with sufficient energy.
Topics that use Collision theory
- Collision theory and activation energy (AQA GCSE)
- Factors which affect the rates of chemical reactions (AQA GCSE)
- Reaction profiles (AQA GCSE)
Related terms
- Activation energy
- Catalyst
- Collision frequency
- Collisions
- Concentration and pressure effects
- Effect of temperature on collision energy
- Energy level diagrams
- Error and uncertainty
Using Collision theory in the exam
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