Atomic Properties
- Atomic Number
- 55
- Atomic Mass
- 132.9100 u
- Electron Configuration
- [Xe] 6s1
- Electronegativity
- 0.79
- Block
- s-block
- Group
- 1
- Period
- 6
Physical Properties
- Phase (STP)
- solid
- Melting Point
- 301.70 K
- Boiling Point
- 944.00 K
- Density
- 1.9300 g/cm³
About Cesium
Most electropositive stable element; defines the second in atomic clocks.
Isotopes of Cesium
Cesium has 1 naturally occurring isotope.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 133Cs | 133 | 132.905452 | 100.00% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)