Le Chatelier’s Principle: Changing Concentration (AQA GCSE Chemistry): Revision Notes
6.2.5 Le Chatelier's Principle: Changing Concentration
The Effect of Concentration Changes on Equilibrium
- According to Le Chatelier's Principle, changing the concentration of reactants or products will cause the equilibrium to shift to oppose that change.
This means that, if the concentration of a product or reactant is increased, the equilibrium will shift towards the direction that reduces the concentration of that substance. If the concentration of a product or reactant is decreased, the equilibrium will shift to increase its concentration.
Example: In the reaction to form ammonia:
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If the concentration of ammonia () is increased by adding more ammonia, the equilibrium will shift to the left to reduce the excess ammonia, thus increasing the concentrations of nitrogen () and hydrogen ().
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If the concentration of ammonia is decreased by removing some from the system, the equilibrium will shift to the right to produce more ammonia.
Limitations: