Haber Process

• Reactants of Haber Process

  • Nitrogen
  • Hydrogen
• Products of Haber Process

  • Ammonia
• Word equation of Haber Process

  Nitrogen + Hydrogen --> Ammonia

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• What type of reaction is the Haber Process

  • Reversible reaction
• Sources of Hydrogen for the haber process

  • Natural gas
• Sources of Nitrogen for the haber process

  • Air
• Where does the Haber Process take place?

  • A reaction vessel
• Describe how the Haber Process is reversible

  • Hydrogen and nitrogen react to form ammonia
  • Ammonia breaks down into nitrogen and hydrogen
• Conditions for the Haber Process

  1. 450 degrees (temperature)
  2. 200 atmospheres (pressure)
  3. Iron catalyst
• Balanced equation for Haber Process

  N2 + 3H2 --> 2NH3
• What ratio is nitrogen and hydrogen in?

  1 : 3
• Use of the Haber Process

  • Manufacture Ammonia
  • To produce nitrogen-based fertilisers
• Process of Haber Process

  Passed over Iron catalyst

  The gases are cooled

  Ammonia condenses, liquified and removed

  The remaining hydrogen and nitrogen are recycled back into the reactor

  
• Explain why ammonia condenses first before the other gases

  ammonia has a higher boiling point
• How is ammonia separated from the other gases?

  • Cools
  • Only Ammonia condenses
• Why is Iron used in the Haber Process?

  • As a catalyst
  • So the reaction speeds up
• How would increasing the temperature of the Haber Process affect the yield of ammonia?

  1. The forward reaction is exothermic.
  2. Increased temperature lowers the yield of ammonia as the endothermic reaction is favoured (reverse reaction).
  3. A lower temperature would decrease the rate of reaction, so thi acts as a compromise
• How does increasing the pressure affect the yield of ammonia?

  • Higher pressure would increase the yield of ammonia because equilibrium shifts to the side with fewer gaseous molecules.
  • The forward reaction produces the least number of gaseous molecules.
• Financial expenses of high pressure

  • High / cost energy
• Pressure on the rate of reaction

  • Greater number of gas molecules per unit volume
  • Frequency of successful collisions increases
  • Higher pressure also increases rate of reaction
• Use of catalyst 


  • Speeds up the rate of the forward and reverse reaction
  • Makes an alternative pathway by lowering the activation energy of the reaction
  • Lowers the energy costs as lower temperatures can be used
• Forward reaction

  • Exothermic
• Backward reaction

  • Endothermic
• Lower temperatures on yield of ammonia

  • Will increase the yield of ammonia
  • But will produce a slower reaction
• State of ammonia after process

  • Liquid
• Factors to consider of Haber Process

  • Atom Economy
  • Yield
  • Energy costs
  • Environmental impacts of nitrogen gas being released
  • Cost of raw materials
• Test for Ammonia using litmus paper

  • Damp litmus paper
  • Turns blue (is a base)