Element: Neon
General data
| Element name | Neon |
|---|---|
| Chemical symbol | Ne |
| Atomic number Z | 10 |
| Year discovered | 1898 |
| Standard state (25°C) | Gas |
| Category | Noble gas |
| Block | p |
| Atomic mass | 20.180 |
| CPK color | #B3E3F5 |
Physical properties
| Melting point | 24.56 K (-248.59 °C) |
|---|---|
| Boiling point | 27.07 K (-246.08 °C) |
| Density | 0.0008999 g/cm³ |
Energy properties
| First ionization energy | 21.565 eV |
|---|---|
| Electron affinity | no data |
Atomic structure
| Protons | 10 (Atomic number) |
|---|---|
| Neutrons (Ne-20, most abundant isotope) | 10 |
| Electrons | 10 |
| Electron configuration | [He] 2s² 2p⁶ |
| Oxidation states | no data |
| Electronegativity (Pauling) | no data |
| Atomic radius (van der Waals) | 154 pm |
Ionization energies - NIST ASD (10 states)
| State | Charge | Ioniz. energy (eV) | Type |
|---|---|---|---|
| Ne I | 0+ | 21.564541 ± 0.000007 | measured |
| Ne II | 1+ | 40.96297 ± 0.00004 | measured |
| Ne III | 2+ | 63.4233 ± 0.0003 | measured |
| Ne IV | 3+ | 97.19 ± 0.0025 | semi-empirical |
| Ne V | 4+ | 126.247 ± 0.012 | measured |
| Ne VI | 5+ | 157.934 ± 0.005 | measured |
| Ne VII | 6+ | 207.271 ± 0.012 | measured |
| Ne VIII | 7+ | 239.097 ± 0.0019 | semi-empirical |
| Ne IX | 8+ | 1195.8082 ± 0.0004 | calculated |
| Ne X | 9+ | 1362.199256 ± 0.000004 | calculated |
Value type as given by NIST ASD: measured - from evaluated experimental data; calculated - from ab initio calculations (mostly highly ionised atoms that have not been measured; for the simplest ones, e.g. H I, the calculation is more accurate than measurement); semi-empirical - from interpolation, extrapolation or another semi-empirical method.
Photos
Isotopes (20)
| A | N | Half-life | Decay |
|---|---|---|---|
| Ne-15 | 5 | unbound (resonance) | 2p |
| Ne-16 | 6 | unbound (resonance) | 2p |
| Ne-17 | 7 | 109.1 ms | EC/β⁺ |
| Ne-18 | 8 | 1.6643 s | EC/β⁺ |
| Ne-19 | 9 | 17.2569 s | EC/β⁺ |
| Ne-20 | 10 | stable | - |
| Ne-21 | 11 | stable | - |
| Ne-22 | 12 | stable | - |
| Ne-23 | 13 | 37.15 s | β⁻ |
| Ne-24 | 14 | 3.38 min | β⁻ |
| Ne-25 | 15 | 602 ms | β⁻ |
| Ne-26 | 16 | 196 ms | β⁻ |
| Ne-27 | 17 | 30.9 ms | β⁻ |
| Ne-28 | 18 | 18.7 ms | β⁻ |
| Ne-29 | 19 | 14.0 ms | β⁻ |
| Ne-30 | 20 | 7.3 ms | β⁻ |
| Ne-31 | 21 | 3.4 ms | β⁻ |
| Ne-32 | 22 | 4.5 ms | β⁻ |
| Ne-33 | 23 | < 180 ns | n |
| Ne-34 | 24 | unknown | β⁻ |
Data sources
- PubChem Periodic Table API - Retrieved on 29 June 2026 - licence: CC0
- IUPAC CIAAW - Abridged Standard Atomic Weights 2024 - Table version: 2024 - licence: Public domain
- NNDC Wallet Cards 2023 - Data as of 15 October 2024 - licence: Public domain
- NIST Atomic Spectra Database (ASD) - Retrieved on 29 June 2026 - licence: © U.S. Secretary of Commerce
- Images of Elements - Retrieved on 29 June 2026 - licence: CC BY 3.0