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Reactive nonmetals

Nitrogen

A diatomic gas making up most of Earth's atmosphere.

Atomic #7Mass14.007Blockp-blockPeriod2Group15
N7 · 14.007
3D Atom Explorer

Inside the Nitrogen atom

Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Nitrogen atom step by step.

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Electron configuration

[He] 2s2 2p3

A neutral Nitrogen atom has 7 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.

Shell distribution

Shell 12 e⁻Shell 25 e⁻

Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.

Properties

Physical & atomic properties

State (room temp)
Gas
Melting point
63 K (-210 °C)
Boiling point
77 K (-196 °C)
Density
0.0012506 g/cm³
Electronegativity
3.04 Pauling
Atomic radius
65 pm
1st ionization energy
1402 kJ/mol
Category
Reactive nonmetals
History

Discovery & naming

Discovered
1772
Discovered by
Daniel Rutherford
Origin of name
Greek 'nitron genes', forming saltpetre.

Notable uses

Fertilizers, explosives, and an inert protective atmosphere.

Cosmic origin

Where Nitrogen comes from

Stellar fusion and dying stars

Cycled out of the CNO fusion cycle and shed by dying low- and intermediate-mass stars.

Simplified origin map — many elements form through more than one astrophysical pathway.

Summary

Atomic number
7
Atomic mass
14.007
Category
Reactive nonmetals
Group · Period
15 · 2
Block
p-block
Shells
2 · 5