Chemical equilibrium

• Chemical Equilibrium


  Kc Constant (concentrations at equilibrium)
• Effects of Le Chatelier's Principle

  2H, N₂ ⇌ 2NH₃
• Reversible reaction


  Dynamic reaction
• Chemical equilibrium


  Le Chatelier's Principle
• The Haber Process is an industrial application
• Increase concentration of N₂


  Decrease concentration of the reactants
• Increase temperature


  Endothermic reaction favoured, forward reaction increases
• Decrease temperature


  Exothermic reaction favoured, backward reaction increases
• Increase pressure


  Forward reaction favoured for gas products
• Catalyst has no effect on equilibrium, it speeds up both forward and backward reactions equally
• Equilibrium constant Kc


  Kc = [Products] / [Reactants]
• Using ICE tables to calculate Kc


  1. Initial

  2. Change

  3. Equilibrium
• Optimum conditions for the Haber Process are: high pressure, moderate temperature
• Industrial applications of the Haber Process


  • Ammonia fertilisers
  • Cleaning agents
• The Contact Process


  2SO₂ + O₂ ⇌ 2SO₃
• Optimum conditions for the Contact Process are: high pressure, low temperature
• Actual conditions for the Contact Process are: high pressure, moderate temperature
• Adding HCl


  Backward reaction is used up
• Adding FeCl₃


  Forward reaction is used up
• Heating the reaction mixture

  Endothermic reaction is favoured
• Cooling the reaction mixture

  Exothermic reaction is favoured