Cesium Electron Configuration
Cesium (Cs) · 55 electrons · Alkali metal
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s1
Noble gas notation: [Xe] 6s1
Orbital diagram
↑↓
1s↑↓
2s↑↓↑↓↑↓
2p↑↓
3s↑↓↑↓↑↓
3p↑↓↑↓↑↓↑↓↑↓
3d↑↓
4s↑↓↑↓↑↓
4p↑↓↑↓↑↓↑↓↑↓
4d↑↓
5s↑↓↑↓↑↓
5p↑
6s- Valence electrons
- 1
- Unpaired electrons
- 1
- Block
- s-block
- Magnetism (atom)
- paramagnetic
Electrons per shell
| K (n = 1) | 2 |
|---|---|
| L (n = 2) | 8 |
| M (n = 3) | 18 |
| N (n = 4) | 18 |
| O (n = 5) | 8 |
| P (n = 6) | 1 |
Cesium ion configurations
| Ion | Electrons | Configuration |
|---|---|---|
| Cs+ | 54 | [Kr] 4d10 5s2 5p6 |
How to write it
Place 55 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. Cesium sits in period 6, group 1, in the s-block, so its last electron enters an s subshell. Replacing the inner electrons with the previous noble gas gives the shorthand [Xe] 6s1.
Try cesium and its ions in the calculator, or see the full cesium data sheet.
Cesium electron configuration FAQ
What is the electron configuration of cesium?
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 6s¹. Shorthand (noble gas) notation: [Xe] 6s¹.
What is the noble gas configuration of cesium?
[Xe] 6s¹. The bracket stands for the Xe core electrons.
How many valence electrons does cesium have?
1 (outer shell (n = 6)).
How many unpaired electrons does cesium have?
1 in the ground state, following Hund’s rule. An atom with unpaired electrons is paramagnetic.
What is the electron configuration of Cs+?
[Kr] 4d¹⁰ 5s² 5p⁶ (54 electrons).