Question

Write down the reaction when ammonia reacts with atmospheric oxygen in the presence of a catalyst.

Answer 1

Hint:Ammonia is a compound formed from nitrogen and hydrogen. It has a pungent odor. Kidney secrete ammonia and helps in the neutralization of the acid in the body. It forms ammonium hydroxide when it gets dissolved in water. It is a gas. It is considered as a Lewis base.

Complete step by step answer:

The molecular formula of ammonia is ${\text{N}}{{\text{H}}_3}$. It has the ability to donate electrons, hence considered as Lewis base. In an acid, ammonia reacts and forms ammonium salt, i.e. ammonium chloride. The lone pair of nitrogen is responsible for making ammonia a base.
Ammonia molecule is of trigonal pyramidal shape. It is a polar molecule. It readily forms hydrogen bonds which is the reason for solubility of ammonia in water. Reaction of ammonia with water is an exothermic reaction. It is also considered as a weak acid in some cases. Thus it is referred to as an amphoteric compound.
When ammonia reacts with atmospheric oxygen, it gives nitric oxide and water molecules. The complete balanced chemical equation is given below:
$4{\text{N}}{{\text{H}}_3} + 5{{\text{O}}_2}\xrightarrow[{1100{\text{K}}}]{{{\text{Pt}}}}4{\text{NO}} + 6{{\text{H}}_2}{\text{O}}$
Four moles of ammonia reacts with five moles of oxygen to give four moles of nitric oxide and six moles of water molecules. This occurred in the presence of platinum catalyst at $1100{\text{K}}$.

Note:
The reaction is a type of displacement reaction since oxygen displaces hydrogen of ammonia. This is also a redox reaction because the nitrogen is being oxidized with the addition of oxygen. Moreover oxygen molecules gain hydrogen to form water molecules.