Nitrogen (N)

Colorless gas

Nitrogen makes up 78% of Earth's atmosphere and is essential for building proteins and DNA, and with three unpaired electrons in its 2p shell, nitrogen forms strong triple bonds (N≡N) making it relatively inert at room temperature. It is fixed by bacteria and used extensively in fertilizers.

Key metrics

Density0.0012506g/cm³

Melting point63.15K

Boiling point77.36K

Electronegativity3.04Pauling

Discovery

1772discovered

Discovered by: Daniel Rutherford
Reactivity profile: Stable diatomic gas
Reactivity: Low
Bonding: Covalent

Electron configuration

\textcolor{#6b7280}{[He]}\; \textcolor{#ef4444}{2_{s}^{2}}\; \textcolor{#3b82f6}{2_{p}^{3}}

[He] 2s2 2p3

Wave function

\Psi_{\text{N}} \approx \frac{1}{\sqrt{7!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_7(\mathbf{r}_7) \right|

Probability density $|\Psi|^2$ across the N valence shell.

Crystal structure

Hexagonal Close-Packed

Lattice constantsa 1.00 · b 1.00 · c 1.63

Cell anglesα 90° · β 90° · γ 120°

Coordination number12

Atoms per cell2

Atomic packing factor0.74

Physical properties

Atomic radius: 56 pm
Ionization energy: 1402 kJ/mol
Electron affinity: -7 kJ/mol
Crystal structure: Hexagonal close-packed (hcp)

Oxidation states

-3+3+5

Acid/base

Neutral

Strongly acidicStrongly basic

State at 25 °CGas

63.15 K77.36 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

444.7nmN IIViolet70%

500.5nmN I (green)Cyan100%

568.0nmN IYellow50%

Dominant line 500.5 nmRange 445–568 nmTransitions 3