Characteristics of nitrogen
Nitrogen is the element of the periodic table of symbol N, and of atomic number 7. This means that its nucleus is formed by 7 protons (apart from neutrons), with 7 electrons around it. At room temperature nitrogen is found in the form of gas, which is odourless, colourless, and very light.
Moreover, this gas is characterised by being very reactive, as it reacts with almost every element in the periodic table (except for noble gases). In fact, the chemical bonds present in the N2 molecule are characterised by being the second strongest chemical bonds.
Nitrogen becomes liquid at a temperature of -195.79ºC and freezes at -210ºC. Because of being colourless, liquid nitrogen is similar, in appearance, to water, even is it is 80% denser than the latter.
Nitrogen is a very common element in the universe as on Earth. It is considered the seventh most abundant element in the universe.
In diatomic form, N2 is the most abundant gas in the terrestrial atmosphere, forming approximately a 78% of the latter (the rest is oxygen in 21%, and a small percentage formed by a great variety of elements).
Apart from this, nitrogen is found on some essential components of a living organism, such as proteins, amino acids, DNA or RNA… It is the fourth most common element in the human body, and it forms approximately a 3% of its mass.
Uses of nitrogen
- A wide use of nitrogen is the production of nitrates and ammonia, which are considered key fertilizers around the world.
- Nitrogen is also used in the manufacturing of high-quality stainless steel.
- It is also used in the manufacturing of many pharmaceutical drugs, including antibiotics.
- Instead of using natural air, many planes and cars used nitrogen to inflate their tires.
- Nitrogen is also used in the fuel of planes to reduce the risk of a fire.
- As liquid nitrogen is extremely cold (-210ºC to 195ºC) it is used in the cryopreservation of biological tissues, cells and blood. It is also used to cool the X-ray detectors and the central processing units in computers when they are warm.
Nitrogen was discovered in 1772 by the chemist Daniel Rutherford, even if he didn’t know the gas he had discovered in reality. He discovered it by extracting the oxygen and carbon dioxide from a bottle, for which only nitrogen remained. Consequently, he observed that this gas didn’t support the combustion of elements or the survival of living organisms.