Making Ammonia & Conditions

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  • Created by: seawhim
  • Created on: 19-05-13 16:13
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  • Making Ammonia
    • Ammonia is a fertilizer. Hydrogen + nitrogen <-> Ammonia (reversible reaction)
      • Nitrogen from air and hydrogen extracted from methane (CH4), into a REACTION VESSEL
        • Ammonia created in reaction, liquefied  (condensing) and then taken off and used.
          • There is a tube leading back to the vessel, for unreacted hydrogen and nitrogen (since it is reversible)
            • Nitrogen from air and hydrogen extracted from methane (CH4), into a REACTION VESSEL
              • Ammonia created in reaction, liquefied  (condensing) and then taken off and used.
                • There is a tube leading back to the vessel, for unreacted hydrogen and nitrogen (since it is reversible)
                • 450 DEGREES CELSIUS
                  • CONDITIONS
                    • TEMPERATURE
                      • HIGH TEMPERATURES favour ENDOTHERMIC (take in heat from surroundings) REACTONS
                        • HIGH RATE OF REACTION
                          • BUT
                            • LOW YIELD
                        • COMPROMISE has to be made between yield, costs and rate of reaction.
                          • For example when making ammonia, low temperatures would produce a higher yield but the rate of reaction would be slow.
                            • Therefore 450 degrees celsius is used for a higher rate of reaction, and since it is reversible the yield is of less importance.
                      • LOW TEMPERATURES favour EXOTHERMIC (releases heat into surroundings) REACTIONS
                        • LOW RATE OF REACTION
                          • BUT
                            • HIGH YIELD
                        • COMPROMISE has to be made between yield, costs and rate of reaction.
                          • For example when making ammonia, low temperatures would produce a higher yield but the rate of reaction would be slow.
                            • Therefore 450 degrees celsius is used for a higher rate of reaction, and since it is reversible the yield is of less importance.
                    • PRESSURE
                      • HIGH PRESSURE favours the direction of reaction which  produces the least number of molecules, so in ammonia a higher pressure creates more ammonia because there are 4 molecules on the left and 2 on the right.
                        • High pressure = higher yield & rate of reaction
                      • LOWER PRESSURE favours the reaction of less molecules (there's more room, they are not pushed together, split apart instead)
                        • Low pressure = low yield & low rate of reaction
                    • CATALYST SPEEDS UP RATE OF REACTION
                    • Equilibrium is when reactions occur at the same rate in each direction
                • IRON CATALYST
                  • CONDITIONS
                    • TEMPERATURE
                      • HIGH TEMPERATURES favour ENDOTHERMIC (take in heat from surroundings) REACTONS
                        • HIGH RATE OF REACTION
                          • BUT
                            • LOW YIELD
                      • LOW TEMPERATURES favour EXOTHERMIC (releases heat into surroundings) REACTIONS
                        • LOW RATE OF REACTION
                          • BUT
                            • HIGH YIELD
                    • PRESSURE
                      • HIGH PRESSURE favours the direction of reaction which  produces the least number of molecules, so in ammonia a higher pressure creates more ammonia because there are 4 molecules on the left and 2 on the right.
                        • High pressure = higher yield & rate of reaction
                      • LOWER PRESSURE favours the reaction of less molecules (there's more room, they are not pushed together, split apart instead)
                        • Low pressure = low yield & low rate of reaction
                    • CATALYST SPEEDS UP RATE OF REACTION
                    • Equilibrium is when reactions occur at the same rate in each direction
                • PRESSURE OF 200 ATMOSPHERES
            • 450 DEGREES CELSIUS
              • IRON CATALYST
                • PRESSURE OF 200 ATMOSPHERES
                • N2+3H2<->2NH3

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