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.

Example: In the reaction to form ammonia:

• If the concentration of ammonia ($NH3$) is increased by adding more ammonia, the equilibrium will shift to the left to reduce the excess ammonia, thus increasing the concentrations of nitrogen ($N2$) and hydrogen ($H2$).

  

• If the concentration of ammonia is decreased by removing some from the system, the equilibrium will shift to the right to produce more ammonia.