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**1. History and Production of Nitrogen:**
– Nitrogen compounds have a long history, known since ancient times.
– Alchemists like Daniel Rutherford, Carl Wilhelm Scheele, Henry Cavendish, and Joseph Priestley contributed to the study of nitrogen.
– Antoine Lavoisier named nitrogen azote due to its asphyxiant nature.
– Elemental nitrogen is produced from air using pressure swing adsorption technology.
– About 2/3 of commercially produced nitrogen is used as an inert gas.
– Nitrogen is used in various industrial compounds like ammonia and nitric acid.
– The triple bond in elemental nitrogen dominates its chemistry.
– Nitrogen is a key component in fertilizers and energy storage.

**2. Applications and Properties of Nitrogen:**
– Nitrogen is present in amino acids, nucleic acids, and ATP in organisms.
– It is a constituent of major pharmacological drug classes, including antibiotics.
– Nitrogen-containing drugs like nitroglycerin and caffeine have significant medical uses.
– Nitrogen is used in high-strength fabrics like Kevlar and superglue.
– Synthetic ammonia and nitrates are essential industrial fertilizers.
– Atomic properties of nitrogen include a covalent radius of 71±1pm and a Van der Waals radius of 155pm.
– Nitrogen has a thermal conductivity of 25.83×10.
– Nitrogen is the 7th most abundant element in the Milky Way and the Solar System.
– It forms about 78% of Earth’s atmosphere and is a common element in the universe.

**3. Isotopes and Chemical Properties of Nitrogen:**
– Nitrogen has two stable isotopes: N-14 and N-15.
– N-14 makes up 99.634% of natural nitrogen, while N-15 makes up 0.366%.
– Nitrogen has high electronegativity and forms various compounds like nitrides.
– It lacks simple cationic chemistry due to high ionization energies.
– Nitrogen forms multiple bonds with carbon, oxygen, or other nitrogen atoms.
– Nitrogen shows similarities to carbon, oxygen, and its vertical pnictogen neighbors.
– It has parallels in chemistry with ammonia and water but differs significantly from its heavier congeners.

**4. Thermal and Physical Properties of Nitrogen:**
– Nitrogen’s properties include density, specific heat, dynamic viscosity, kinematic viscosity, and thermal conductivity.
– The properties vary with temperature from 100K to 1300K.
– Nitrogen’s properties make it distinct from its vertical neighbors and are crucial for various industrial and scientific applications.
– Nitrogen condenses at 77K and freezes at 63K.
– It has a thermal conductivity of 25.83×10.

**5. Nitrogen in NMR Spectroscopy, Allotropes, and Chemistry:**
– Nitrogen has an integer nuclear spin of one, leading to wider spectra.
– Low natural abundance reduces sensitivity, but isotopic enrichment can alleviate this.
– Nitrogen-13 is used in positron emission tomography, and Nitrogen-16 is a dominant radionuclide in nuclear reactors.
– Nitrogen polymerizes into various crystal structures under extreme conditions.
– Dinitrogen complexes are important in biological processes and exist for almost all transition metals.
– Nitrogen forms bonds with almost all elements except noble gases and creates a variety of binary compounds with different properties.

Nitrogen (Wikipedia)

Nitrogen is a chemical element; it has symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colorless and odorless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element in air. Because of the volatility of nitrogen compounds, nitrogen is relatively rare in the solid parts of the Earth.

Nitrogen, 7N
A transparent liquid, with visible evaporation, being poured
Liquid nitrogen (N2 at below −196 °C)
Allotropessee § Allotropes
Appearancecolorless gas, liquid or solid
Standard atomic weight Ar°(N)
  • [14.0064314.00728]
  • 14.007±0.001 (abridged)
Nitrogen in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


Atomic number (Z)7
Groupgroup 15 (pnictogens)
Periodperiod 2
Block  p-block
Electron configuration[He] 2s2 2p3
Electrons per shell2, 5
Physical properties
Phase at STPgas
Melting point(N2) 63.23 K ​(−209.86 °C, ​−345.75 °F)
Boiling point(N2) 77.355 K ​(−195.795 °C, ​−320.431 °F)
Density (at STP)1.2506 g/L at 0 °C, 1013 mbar
when liquid (at b.p.)0.808 g/cm3
Triple point63.151 K, ​12.52 kPa
Critical point126.21 K, 3.39 MPa
Heat of fusion(N2) 0.72 kJ/mol
Heat of vaporisation(N2) 5.57 kJ/mol
Molar heat capacity(N2) 29.124 J/(mol·K)
Vapour pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 37 41 46 53 62 77
Atomic properties
Oxidation states−3, −2, −1, 0, +1, +2, +3, +4, +5 (a strongly acidic oxide)
ElectronegativityPauling scale: 3.04
Ionisation energies
  • 1st: 1402.3 kJ/mol
  • 2nd: 2856 kJ/mol
  • 3rd: 4578.1 kJ/mol
  • (more)
Covalent radius71±1 pm
Van der Waals radius155 pm
Color lines in a spectral range
Spectral lines of nitrogen
Other properties
Natural occurrenceprimordial
Crystal structurehexagonal
Hexagonal crystal structure for nitrogen
Thermal conductivity25.83×10−3 W/(m⋅K)
Magnetic orderingdiamagnetic
Speed of sound353 m/s (gas, at 27 °C)
CAS Number17778-88-0
7727-37-9 (N2)
DiscoveryDaniel Rutherford (1772)
Named byJean-Antoine Chaptal (1790)
Isotopes of nitrogen
Main isotopes Decay
abun­dance half-life (t1/2) mode pro­duct
13N trace 9.965 min β+ 13C
14N 99.6% stable
15N 0.4% stable
16N synth 7.13 s β 16O
βα<0.01% 12C
 Category: Nitrogen
| references

It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772 and independently by Carl Wilhelm Scheele and Henry Cavendish at about the same time. The name nitrogène was suggested by French chemist Jean-Antoine-Claude Chaptal in 1790 when it was found that nitrogen was present in nitric acid and nitrates. Antoine Lavoisier suggested instead the name azote, from the Ancient Greek: ἀζωτικός "no life", as it is an asphyxiant gas; this name is used in a number of languages, and appears in the English names of some nitrogen compounds such as hydrazine, azides and azo compounds.

Elemental nitrogen is usually produced from air by pressure swing adsorption technology. About 2/3 of commercially produced elemental nitrogen is used as an inert (oxygen-free) gas for commercial uses such as food packaging, and much of the rest is used as liquid nitrogen in cryogenic applications. Many industrially important compounds, such as ammonia, nitric acid, organic nitrates (propellants and explosives), and cyanides, contain nitrogen. The extremely strong triple bond in elemental nitrogen (N≡N), the second strongest bond in any diatomic molecule after carbon monoxide (CO), dominates nitrogen chemistry. This causes difficulty for both organisms and industry in converting N2 into useful compounds, but at the same time it means that burning, exploding, or decomposing nitrogen compounds to form nitrogen gas releases large amounts of often useful energy. Synthetically produced ammonia and nitrates are key industrial fertilisers, and fertiliser nitrates are key pollutants in the eutrophication of water systems. Apart from its use in fertilisers and energy stores, nitrogen is a constituent of organic compounds as diverse as aramids used in high-strength fabric and cyanoacrylate used in superglue.

Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids (DNA and RNA) and in the energy transfer molecule adenosine triphosphate. The human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. The nitrogen cycle describes the movement of the element from the air, into the biosphere and organic compounds, then back into the atmosphere. Nitrogen is a constituent of every major pharmacological drug class, including antibiotics. Many drugs are mimics or prodrugs of natural nitrogen-containing signal molecules: for example, the organic nitrates nitroglycerin and nitroprusside control blood pressure by metabolizing into nitric oxide. Many notable nitrogen-containing drugs, such as the natural caffeine and morphine or the synthetic amphetamines, act on receptors of animal neurotransmitters.

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