Open In App

Dinitrogen – Definition, Preparation, Properties, Uses

Last Updated : 11 Nov, 2021
Like Article

Nitrogen is the lightest element in Periodic Table Group 15, also known as the pnictogens. Dinitrogen, a colourless and odourless diatomic gas with the formula N2, is formed when two atoms of the element join together at STP. 

Dinitrogen is the most abundant uncombined element, accounting for around 78% of the Earth’s atmosphere. Nitrogen is found in all living things, most notably in amino acids, nucleic acids (DNA and RNA), and adenosine triphosphate, an energy transfer molecule. 

The human body contains approximately 3% nitrogen by mass. The nitrogen cycle describes the movement of nitrogen from the atmosphere to the biosphere and organic compounds, and then back to the atmosphere.


Dinitrogen constitutes 78% of the earth’s atmosphere, making it the most abundant element in the atmosphere and the seventh most abundant uncombined element in the universe. Daniel Rutherford, a Scottish physician, discovered this element for the first time in 1772. This chemical element’s symbol is N, and its atomic number is 7.


Dinitrogen is commercially produced by liquefaction and fractional distillation of air. Liquid dinitrogen separates first, leaving liquid oxygen behind. Dinitrogen is synthesized in the laboratory by reacting an aqueous solution of ammonium chloride with sodium nitrite.

NH4CI(aq) + NaNO2 (aq) → N2 (g) + 2H2O(l) + NaCl (aq)

In this reaction, small amounts of NO and HNO3 are formed; these impurities can be removed by passing the gas through aqueous sulphuric acid containing potassium dichromate. It can also be made by thermally decomposing ammonium dichromate.

(NH4)2Cr2O7 → N2 + 4H2O + Cr2O3

The thermal decomposition of sodium or barium azide can yield very pure nitrogen.

Ba(N3)2 → Ba + 3N2

Properties of Dinitrogen

  • Dinitrogen is a non-toxic gas that is colourless, odourless, and tasteless.
  • The atom of nitrogen has two stable isotopes.
  • It has very low water solubility and low freezing and boiling points.
  • Because of the high bond enthalpy of the N≡N bond, dinitrogen is relatively inert at room temperature.
  • Reactivity, on the other hand, increases rapidly as the temperature rises. At higher temperatures, it directly combines with some metals to form predominantly ionic nitrides and covalent nitrides with nonmetals.
  • Nitrogen condenses to form a colourless liquid, which solidifies to form a snow-like mass.
  • At room temperature, Nis almost non-reactive. It does not burn and does not support combustion. The chemical inertness of N2 at room temperature is due to the molecule’s high stability.
  • It has been known to react with metals such as lithium, alkali metals, and calcium under very mild conditions. Such reactions are known to be surface tarnishing reactions, with the final bulk product being a metal nitride, such as Li3N.

Reactions with Dinitrogen 

  • Combination with Electropositive Metals

At high temperatures, it combines with some highly electropositive metals to form nitrides. At low temperatures, lithium nitride forms slowly, but quickly at high temperatures. Magnesium and aluminium continue to burn in a nitrogen atmosphere, forming nitrides. When calcium, strontium, and barium are red hot, they react with N2.

6Li+N2  →  2Li3N2

3Mg+N2  →  Mg3N2

2Al+N2  →   2AlN

3Ca+N2  →   Ca3N2

  • Combination with O

In the presence of an electric arc (above 3273K), N2 combines with O2 to form nitric oxide.

N+O2 → 2NO

Uses of Dinitrogen

  • Dinitrogen is primarily used in the production of ammonia and other nitrogen-containing industrial chemicals (e.g., calcium cyanamide).
  • It is also used in situations where an inert atmosphere is required (e.g., in the iron and steel industry, inert diluent for reactive chemicals).
  • Liquid dinitrogen is a refrigerant that is used to preserve biological materials, food, and cryosurgery.

Nitrogen Cycle

The nitrogen cycle is the movement of nitrogen in various forms throughout nature. Nitrogen is required for life on Earth because it is a component of proteins and nucleic acids. Although nitrogen gas constitutes 78% of the atmosphere by volume, this abundant reservoir exists in an unusable form for most organisms. 

  • Nitrogen is made available to plants through a series of microbial transformations, which in turn sustain all animal life. Nitrogen fixation, nitrogen assimilation, ammonification, nitrification, and denitrification are the classifications for the steps, which are not all sequential.
  • Nitrogen fixation, or the conversion of nitrogen gas into inorganic nitrogen compounds, is primarily accomplished by certain bacteria and blue-green algae. A much smaller amount of free nitrogen is fixed abiotically and through the Haber-Bosch process, which converts it to ammonia.
  • Nitrogen fixation produces nitrates and ammonia, which are incorporated into algae and higher plants’ specialized tissue components. These algae and plants are then consumed by animals, where they are converted into their own body compounds.
  • Microorganisms decompose the remains of all living things and their waste products in the ammonification process, which produces ammonia and ammonium. Foul-smelling putrefactive products may appear under anaerobic, or oxygen-free, conditions, but they, too, are converted to ammonia over time. Depending on soil conditions, ammonia can either leave the soil or be converted into other nitrogen compounds.
  • Nitrification is the process by which nitrifying bacteria convert soil ammonia into nitrates (NO3) that plants can incorporate into their own tissues.

Sample Questions

Question 1: Give some uses of dinitrogen.


It is primarily used in the industrial production of compounds such as ammonia, calcium cyanamide, and others. Dinitrogen is used to create an inert atmosphere in industries such as iron and steel. In the food industry, liquid nitrogen is used as a preservative as well as a refrigerant.

Question 2: Why does nitrogen exhibits a +5 oxidation state, but not form pentahalide?  


Nitrogen has only s and p orbitals when n = 2. It lacks d orbitals, which would allow it to expand its covalence beyond four. As a result, it does not form pentahalide.

Question 3: Why does NO2 dimerize?


NO2 has an even number of valence electrons. It behaves like any other odd molecule. Dimerization converts it to a stable N2O4 molecule with an even number of electrons.

Question 4: What are the major acids which are formed by Nitrogen?


Nitrogen produces oxoacids such as H2N2O2 (hyponitrous acid), HNO2 (nitrous acid), and HNO3 (hydrogen peroxide) (nitric acid).

Question 5: How is dinitrogen produced commercially?


Dinitrogen is commercially produced by liquefaction and fractional distillation of air. Liquid dinitrogen separates first, leaving liquid oxygen behind. In the lab, dinitrogen is made by mixing an aqueous solution of ammonium chloride with sodium nitrite.

Previous Article
Next Article

Similar Reads

Dinitrogen Monoxide Formula - Structure, Properties, Uses, Sample Questions
Nitrous oxide is another name for dinitrogen monoxide. It's an inorganic substance having a simple chemical formula. At room temperature, it is colourless and combustible. It's also a strong oxidant, thus it's quite comparable to the oxygen molecule. Let us look at the dinitrogen monoxide formula with examples in this article. This article also cov
6 min read
Dinitrogen Pentoxide Formula - Structure, Properties, Uses, Sample Questions
Dinitrogen Pentoxide Formula contains  2 nitrogen and 5 oxygen atoms. Nitrogen is one of the most common chemical elements with the symbol N. Its atomic number is 7. It is found in huge quantities in Earth's crust. It is a nonmetal and the lightest member of group 15 of the periodic table. It is used for food preservation and food packing. Nitrogen
5 min read
Dinitrogen Trioxide Formula - Structure, Properties, Uses, Sample Questions
Nitrogen is very essential to life. Daniel Rutherford discovered nitrogen in the year 1772. It belongs to group 15 of the periodic table. Nitrogen is colorless, odorless gas with the symbol N. It has an atomic weight of 14.0067u. The density of nitrogen is 0.001145 g/cm3 with atomic number 7. However, Oxygen supports life on earth. It belongs to th
5 min read
What is Sodium Chloride? - Definition, Preparation, Properties, Uses
Salt's chemical name is sodium chloride. Sodium is an electrolyte that regulates your body's water content. Sodium is also involved in nerve impulses and muscle contractions. Sodium chloride is a medication used to treat or prevent sodium loss caused by dehydration, excessive sweating, or other factors. What is Sodium Chloride (or Common Salt)? It
6 min read
Dioxygen - Definition, Properties, Preparation, Uses
Oxygen is a member of the periodic table's chalcogen group, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements and other compounds. Oxygen is the most abundant element on Earth, and it is the third-most abundant element in the universe after hydrogen and helium. Diatomic oxygen gas now accounts for 20.95
5 min read
Hydrogen Chloride - Definition, Preparation, Properties, Uses
As a hydrogen halide, the compound hydrogen chloride has the chemical formula HCl. It is a colourless gas at ambient temperature that emits white fumes of hydrochloric acid when it comes into contact with air-water vapour. In technology and industry, hydrogen chloride gas and hydrochloric acid are critical. Hydrochloric acid, an aqueous solution of
7 min read
Properties of Acids - Definition, Examples, Properties, Uses
Acids have a corrosive effect. When we cook acidic foods in brass or copper utensils, the metal reacts and corrodes. When copper reacts with acid, it creates copper salt. Copper salts are toxic and taint the flavour of cooked food. This is why we don't keep liquid foods in metallic containers. Tea should also be served in copper mugs. Tin, a brilli
6 min read
Ammonia - Properties, Preparation, Uses, Effects
Ammonia is made up of hydrogen and nitrogen. It is known as ammonium hydroxide in its aqueous form. This inorganic compound has a strong odour. It is dangerous and caustic in its concentrated form. Ammonia has a density of 0.769 kg/m3 at STP, making it lighter than air. It's commonly used as a fertiliser. It's also used in the production of explosi
6 min read
Ozone - Preparation, Properties, Uses, Effects
Ozone is too reactive to stay in the atmosphere at sea level for long. It is formed from atmospheric oxygen in the presence of sunlight at a height of about 20 kilometres. This ozone layer shields the earth's surface from an excess of ultraviolet (UV) radiation. It is an unstable, blue, diamagnetic gas with a distinctive pungent odour that shields
7 min read
Ozone - Properties, Structure, Preparation, Reactions and Uses
Ozone is an irritating light blue gas that, even at low concentrations, is explosive and poisonous. It naturally occurs in small levels in the Earth's stratosphere, where it absorbs solar UV light, which would otherwise cause severe harm to living things on the Earth's surface. Under some conditions, photochemical reactions in the lower atmosphere
8 min read