Making Ammonia Flashcards
Describe the manufacture of ammonia
The purified gasses are passed over a catalyst of iron at a high temperature (about 450oC) and a high pressure (about 200 atmospheres). Some of the hydrogen and nitrogen reacts to form ammonia. The reaction is reversible so ammonia breaks down again into nitrogen and hydrogen.
On cooling, the ammonia liquified and is removed. The remaining hydrogen and nitrogen is recycled
When does a reversible reaction occur?
In a closed system
When is equilibrium reached?
When the reactions occurs at exactly the same rate in each direction
The relative amounts of all the reacting substances at equilibrium depend on….
The conditions of the reaction
What happen to the yield of the temperature is raised?
The yield from the endothermic reaction increases
The yield from the exothermic reaction decreases
What happen to the yield of the temperature is lowered?
The yield from the endothermic reaction decreases
The yield from the exothermic reaction increases
In a gaseous reaction, how will an increase in pressure affect the reaction?
It will favour the reaction that produces the least number of molecules as shown by the symbol equation for the reaction
What is the temperature, the pressure and the rate of the reaction are important when determine what?
The optimum conditions in industrial process, including the Haber process
What are the raw materials for the Harber process?
Nitrogen, which is obtained from the air
Hydrogen, which may be obtained from natural gas or other sources
