What is Ammonia and How is it Used?
Ammonia is a chemical compound of nitrogen and hydrogen with the formula NH3. It is a colourless gas with a distinct pungent smell that can be used for various purposes. In this article, we will explore some of the properties, applications, and history of ammonia.
Properties of Ammonia
Ammonia is the simplest stable compound of nitrogen and hydrogen, and one of the most abundant substances in the universe. It has a boiling point of -33.34Â°C and a melting point of -77.73Â°C. It is highly soluble in water, forming a basic solution called ammonium hydroxide (NH4OH). Ammonia can also act as a weak acid or a weak base, depending on the pH of the solution. Ammonia can form complexes with many metals, such as copper, silver, and iron. It can also react with oxygen to form nitric oxide (NO) and nitrogen dioxide (NO2), which are important components of air pollution and acid rain.
Uses of Ammonia
The major use of ammonia is as a fertilizer. It provides nitrogen, which is essential for plant growth and development. Ammonia can be applied directly to the soil or converted into other forms of nitrogen, such as ammonium nitrate (NH4NO3), ammonium sulfate ((NH4)2SO4), urea ((H2N)2C=O), and ammonium phosphates.
Ammonia is also used in the manufacture of many other products, such as:
- Synthetic fibres, such as nylon and rayon.
- Explosives, such as TNT, nitroglycerin, and nitrocellulose.
- Dyes and pigments.
- Cleansing agents.
- Fuel cells and hydrogen storage.
- Refrigeration and air-conditioning.
- Lifting gas for balloons and airships.
- Soda ash (Na2CO3) and nitric acid (HNO3) by the Solvay process and the Ostwald process respectively.
History of Ammonia
The word ammonia comes from the name of the ancient Egyptian god Amun, who was also known as Ammon. The ancient Egyptians used ammonium chloride (NH4Cl), also called sal ammoniac, as a fertilizer and a dyeing agent. The Romans called the same substance nitrum. The term ammoniac was later used to refer to any substance that emitted ammonia when heated.
Pure ammonia was first prepared by Joseph Priestley in 1774 by passing electric sparks through a mixture of air and hydrogen. He called it alkaline air or volatile alkali. Claude-Louis Berthollet determined its exact composition in 1785. In 1808, Humphry Davy named it ammonia after the ancient source sal ammoniac.
The industrial production of ammonia began in 1913 by the Haber-Bosch process, which combines nitrogen from the air with hydrogen from natural gas or coal under high pressure and temperature in the presence of an iron catalyst. This process was developed by Fritz Haber and Carl Bosch, who received Nobel Prizes for their work. Today, ammonia is one of the most widely produced chemicals in the world.