Important Processes LEARN AS OCR chemistry A

Many important chemical processes exist as equilibrium systems, these include...

• preparation of ammonia from nitrogen and hydrogen in the HABER PROCESS.
• conversion of sulfur dioxide into sulfur trioxide in the CONTACT PROCESS.

N2(g) + 3H2 (g) ----------> 2NH3 (g)           enthalpy= -92 KJ mol-1

• Ammonia is produced by the forward reaction in this equilibrium
• The forward reaction produces fewer gas molecules FAVOURED by using HIGH PRESSURE.
• The forward reaction is EXOTHERMIC, FAVOURED by using a LOW TEMPERATURE.

• Although a low temperature should produce a high equilibrium yield, the reaction would take place too slowly! (at a low rate).
• At low temperatures few N2 and H2…