Factors Affecting Equilibrium

The Acidic Environment‎ > ‎2. Acidic Oxides‎ >

 Identify factors which can affect the equilibrium in a reversible reaction

The following changes to an equilibrium system will have the following effects, with each effect obeying Le Chatelier’s principle by opposing the change:

  • Changes in temperature:
    • If the forward reaction is exothermic, an increase in temperature causes the system to shift in the reverse direction.
    • If the forward reaction is endothermic, an increase in temperature causes the system to shift in the forward direction.
    • The opposite effects would be observed for a decrease in temperature.
  • Changes in concentration:
    • An increase in the concentration of one or more reactants, or a decrease in the concentration of one or more products, causes the system to shift in the forward direction.
    • A decrease in the concentration of one or more of reactants, or an increase of the concentration of one or more products, causes the system to shift in the reverse direction.
  • Changes in pressure (of homogenous gaseous systems):
    • An increase in pressure causes the system to shift in the direction of fewer gas molecules.
    • A decrease in pressure causes the system to shift in the direction of more gas molecules.
    • If the number of particles on each side of the reaction is equal, then a change in pressure has no effect.