Nitrogen and Ammonia

Nitrogen and Its Properties

Nitrogen is a gas that exists as diatomic molecules (N₂) and makes up about 78% of the Earth’s atmosphere.
It is a nonmetal with symbol N and atomic number 7.
Nitrogen is colourless, odourless and tasteless.
At room temperature, it behaves as an inert gas due to the strong triple bond in its diatomic molecule, making it relatively unreactive.

The Nitrogen Cycle is a biogeochemical process through which nitrogen is converted into multiple chemical forms as it circulates in the environment.
The process primarily includes nitrogen fixation, ammonification, nitrification, and denitrification.
Nitrogen is essential for many biological processes; including the production of proteins and DNA.

Ammonia (NH₃) is a useful compound of nitrogen, extensively used in agriculture as a fertilizer due to its high nitrogen content.
Ammonia is produced industrially by the Haber Process which combines nitrogen from the air with hydrogen obtained from natural gas in presence of an iron catalyst.
The equation for the Haber process is: N₂(g) + 3H₂(g) ↔ 2NH₃(g)
This reaction is reversible, operated under conditions of high pressure (200 atm) and a temperature of about 450°C to shift the equilibrium to the right and maximise yield.

While ammonia is valuable in the production of fertilisers, its use also has environmental implications.
Excess usage can lead to eutrophication, a process where water bodies become overly enriched with nutrients, resulting in the excessive growth of algae and other aquatic plants.
This can disrupt normal water systems, leading to a decrease in water oxygen levels and harming aquatic life.

Ammonia vapour can be irritating and harmful to the eyes and respiratory system.
In case of exposure, it’s essential to flush the eyes and skin with plenty of water, and seek medical attention if necessary.
Handling and transportation of ammonia require strict safety measures including the use of personal protective equipment.