Le Chatelier’s Principle

• What does Le Chatelier's Principle state about a system in equilibrium when subjected to a change in conditions?

  The system shifts to resist the change.
• How does raising the temperature affect the yield of an exothermic reaction?


  The yield decreases.
• What happens to the yield of an exothermic reaction when the temperature is lowered?


  The yield increases.
• In an endothermic reaction, what is the effect of raising the temperature on the yield?


  The yield increases.
• What happens to the yield of an endothermic reaction when the temperature is lowered?


  The yield decreases.
• How does an increase in pressure affect reactions involving gases?


  It favors the reaction that produces the least number of gas molecules.
• What is the effect of a decrease in pressure on reactions involving gases?

  It favors the reaction that produces the greater number of gas molecules.
• What occurs if the concentration of a reactant or product is changed in a system at equilibrium?


  The system is no longer in equilibrium.
• What happens to the position of equilibrium if the concentration of a reactant is increased?


  The position of equilibrium shifts to form more products.
• If the concentration of a reactant is decreased, how does the position of equilibrium shift?


  The position of equilibrium shifts to form more reactants.
• What factors determine the optimum conditions in industrial processes?

  • Reaction rates
  • Concentration of reactants and products
  • Temperature and pressure changes
  • Le Chatelier's Principle
• What is Le Chatelier’s Principle?


  If conditions are changed, an equilibrium will shift and try and cancel out the change clip
• What happens in contrast, if fhe concentration of one of the reactants is decreased?


  The position of equilibrium shifts so that more reactants are formed until equilibrium is reached