Collision theory
What Collision theory means in Combined Science GCSE, as defined for AQA.
Definitions of Collision theory
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Reference: AQA
A hypothesis is justified by referring to the frequency or energy of collisions between reacting particles, including the proportion of particles with energy greater than or equal to the activation energy.
Explains how various factors affect rates of reactions, and that reactions can occur only when reacting particles collide with each other and with sufficient energy.
Particles must collide with at least the activation energy for a reaction to occur, and the rate depends on the frequency of these successful collisions.
Used to predict and explain how changing conditions of concentration, pressure and temperature affect the rate of a reaction.
Particles can only react when they collide with enough energy to overcome the activation energy barrier.
Topics that use Collision theory
- Collision theory and activation energy (AQA GCSE)
- Factors which affect the rates of chemical reactions (AQA GCSE)
- Key ideas (AQA GCSE)
Related terms
- Activation energy
- Catalysts
- Action at a distance
- Active site
- Adaptation
- Anaerobic respiration
- Carbon and nitrogen cycles
- Cells
Using Collision theory in the exam
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