Le Chatelier's principle
What Le Chatelier's principle means in Combined Science GCSE, as defined for AQA.
Definitions of Le Chatelier's principle
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Reference: AQA
A principle that predicts how a system at equilibrium responds to a change: the equilibrium shifts in the direction that opposes the change.
Changing temperature, pressure or concentration shifts the position of equilibrium to counteract the change.
The system opposes the temperature change by favouring the reaction that absorbs or releases heat.
The equilibrium shifts to oppose the change when a reactant or product concentration changes.
Topics that use Le Chatelier's principle
- The effect of changing concentration (HT only) (AQA GCSE)
- The effect of changing conditions on equilibrium (HT only) (AQA GCSE)
- The effect of temperature changes on equilibrium (HT only) (AQA GCSE)
Related terms
- Concentration changes and equilibrium position
- Dynamic equilibrium
- Effect of pressure and concentration on equilibrium
- Effect of temperature on equilibrium
- Endothermic forward reaction
- Equilibrium
- Interpreting equilibrium data
- Interpreting tabulated and graphical data
Using Le Chatelier's principle in the exam
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