Science
Le chatelier's principle.
Definition
Le Chatelier's principle states that if a stress is applied to a system at equilibrium, the system will shift in the direction that partially counteracts the stress and re-establishes equilibrium. Stresses include changes in concentration, pressure, volume, or temperature.
Examples
Real-world.
- 1 Adding more N₂ to the Haber process shifts equilibrium toward producing more NH₃
- 2 Increasing temperature of an exothermic reaction shifts equilibrium toward the reactants
- 3 Decreasing volume of a gas-phase reaction shifts equilibrium toward the side with fewer moles of gas
Key Fact
The system shifts to oppose the applied stress; a catalyst does NOT shift equilibrium—it only speeds up both directions equally.