3.2.3

• Dynamic equilibrium


  When the concentrations of reactants and products remain constant, even though the amounts are different
• Equilibrium only occurs in closed systems
• Le Chatelier's Principle


  If a reaction at equilibrium is subject to a change, the position of equilibrium will move to counteract the change
• Equilibrium constant (Kc)


  A measure of the relative concentrations of reactants and products at equilibrium
• Calculating KC


  Products concentration divided by reactants concentration, with each concentration raised to the power of its stoichiometric coefficient
• Effect of KC

  Temperature - changes

  Pressure - stays same

  Concentration - stays same

  Add catalyst - stays same
• Exothermic forward reaction


  Increasing temperature shifts equilibrium backwards, decreasing KC
• Endothermic forward reaction


  Increasing temperature shifts equilibrium forwards, increasing KC