Neon (Ne)

Colorless gas

Neon is the gas that gives orange-red glow to advertising signs and indicator lights, and with a completely filled 2p⁶ shell, neon is chemically inert and has the narrowest liquid range of any element. It emits characteristic orange-red light when electrically excited at low pressure.

Key metrics

Density9.00e-4g/cm³

Melting point24.56K

Boiling point27.1K

Electronegativity0Pauling

Discovery

1898discovered

Discovered by: William Ramsay
Reactivity profile: Chemically Inert
Reactivity: Low
Bonding: Covalent

Electron configuration

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

[He] 2s2 2p6

Wave function

\Psi_{\text{Ne}} \approx \frac{1}{\sqrt{10!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{10}(\mathbf{r}_{10}) \right|

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

Crystal structure

Face-Centered Cubic

Lattice constantsa = 1.00

Cell anglesα = β = γ = 90°

Coordination number12

Atoms per cell4

Atomic packing factor0.74

Physical properties

Atomic radius: 38 pm
Ionization energy: 2080 kJ/mol
Electron affinity: 0 kJ/mol
Crystal structure: Face-centered cubic (fcc)

Oxidation states

Acid/base

Neutral

Strongly acidicStrongly basic

State at 25 °CGas

24.56 K27.1 K298 K

Emission spectrum

5 transitions

380450500550600650700780

VioletBlueGreenYellowRed

540.1nmNe I (green)Green70%

585.2nmNe I (yellow)Yellow100%

588.2nmNe IYellow50%

640.2nmNe I (red)Red90%

667.8nmNe I (red)Red60%

Dominant line 585.2 nmRange 540–668 nmTransitions 5