Chemical Equilibrium

• State Le Chatelier's Principle

  When the equilibrium in a closed system is disturbed, the system will re-instate a new equilibrium by favoring the reaction that will oppose the disturbance.
• Reversible Reaction

  A reaction is reversible when products can be converted back to reactants and vice versa.
• Chemical Equilibrium 


  It is a dynamic equilibrium when the rate of the forward reaction equals the rate of the reverse reaction.
• How to Answer Le Chateliers Principle Questions


  1.Identify the change.

  2. Reaction of the system (how will the system counteract the change?)

  3. Favoured reaction.

  4. Effect
• Kc value only changes with what variable?

  TEMPERATURE
• Kc < 1 =?

  Reverse reaction favored,

  [Products] < [Reagents]
• Kc > 1 =?

  Forward reaction favored,

  [products]> [reagents]
• Open System

  An open system continuously interacts with its environment.
• Closed system


  Is isolated from its surroundings.
• Factors that Influence the position of an equilibrium.

  • pressure (gases only)
  • concentration
  • temperature.