Argon Electron Configuration
Argon (Ar) · 18 electrons · Noble gas
1s2 2s2 2p6 3s2 3p6
Noble gas notation: [Ne] 3s2 3p6
Orbital diagram
↑↓
1s↑↓
2s↑↓↑↓↑↓
2p↑↓
3s↑↓↑↓↑↓
3p- Valence electrons
- 8
- Unpaired electrons
- 0
- Block
- p-block
- Magnetism (atom)
- diamagnetic
Electrons per shell
| K (n = 1) | 2 |
|---|---|
| L (n = 2) | 8 |
| M (n = 3) | 8 |
How to write it
Place 18 electrons into subshells in the Aufbau order (1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p), filling s with 2, p with 6, d with 10 and f with 14. Argon sits in period 3, group 18, in the p-block, so its last electron enters a p subshell. Replacing the inner electrons with the previous noble gas gives the shorthand [Ne] 3s2 3p6.
Try argon and its ions in the calculator, or see the full argon data sheet.
Argon electron configuration FAQ
What is the electron configuration of argon?
1s² 2s² 2p⁶ 3s² 3p⁶. Shorthand (noble gas) notation: [Ne] 3s² 3p⁶.
What is the noble gas configuration of argon?
[Ne] 3s² 3p⁶. The bracket stands for the Ne core electrons.
How many valence electrons does argon have?
8 (full outer shell).
How many unpaired electrons does argon have?
0 in the ground state, following Hund’s rule. With all electrons paired, the atom is diamagnetic.