The Effect of Changing Concentration (OCR GCSE Chemistry A, Combined (Gateway Science Suite)): Revision Notes
📚 Revision Notes
6.2.5 The Effect of Changing Concentration
The concentration of reactants or products in a reaction can affect the position of equilibrium. According to Le Chatelier's Principle, if the concentration of a reactant or product is changed, the equilibrium will shift to counteract this change.
- Increasing the concentration of reactants: The system will shift towards the products (right) to use up the extra reactants and produce more products.
- Decreasing the concentration of reactants: The system will shift towards the reactants (left) to produce more reactants and restore balance.
- Increasing the concentration of products: The equilibrium will shift towards the reactants (left) to reduce the concentration of products.
- Decreasing the concentration of products: The system will shift towards the products (right) to produce more products.
lightbulbExample
Example: In the formation of ammonia:
→ If more nitrogen or hydrogen is added, the equilibrium shifts to the right to produce more ammonia.
→ If ammonia is removed, the equilibrium also shifts to the right to produce more ammonia.