Le Chatelier's principle
What Le Chatelier's principle means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Le Chatelier's principle
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Reference: OCR
When a system at equilibrium is subjected to a change in conditions, the position of equilibrium shifts to oppose that change.
The system opposes the temperature change by favouring the direction that absorbs or releases heat.
When a system at equilibrium is disturbed, the position of equilibrium shifts to oppose the change.
A system at equilibrium shifts to oppose a change in conditions.
Topics that use Le Chatelier's principle
- Chemical equilibria and Le Chatelier's principle (AQA A-Level)
- Chemical equilibrium (OCR A-Level)
- How far? (OCR A-Level)
Related terms
- closed system
- constant concentrations
- dynamic equilibrium
- equal forward and reverse rates
- Equilibrium constant Kc
- homogeneous equilibria
- position of equilibrium
- Temperature dependence of Kc
Using Le Chatelier's principle in the exam
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