Chemical Reactions in Gas Phase – Ammonia Synthesis


Ammonia synthesis process

Ammonia is a widely used material, such as fertilizers, plastic materials, medicines, and daily necessities. Currently, ammonia is being mass-produced at factories. However, when we did not know how to synthesize ammonia in the past, we thought that ammonia was the only organism that could produce it. The synthesis process of ammonia is as follows.

N2 + 3H2 -> 2NH3 ΔH = -92 KJ/mol

That is, 1 volume of nitrogen gas and 3 volumes of hydrogen gas produce 2 volumes of ammonia. ΔH indicates the transfer of energy in the reaction course, and (-) indicates that the reaction is exothermic.
According to the principle of Le Chatelier, more ammonia can be obtained at higher pressures and lower temperatures.

Scientists can increase the pressure as much as possible but can not lower the temperature. For the chemical reaction to occur, the particles must collide with one another over a certain speed. In this case, using a catalyst can reduce the energy required for the collision.
Currently, ammonia is made in a huge reaction vessel with high pressure containing nitrogen gas, hydrogen gas, and catalyst.