| Cs | Cesium | Alkali Metal |
| Atomic number: | 55 | Atomic weight: | 132.90543 | ||
| Shells: | 2,8,18,18,8,1 | Orbitals: | [Xe] 6s1 | ||
| Melting point: | 28.4°C | Boiling point: | 669.3°C | ||
| Covalent radius: | 2.35 | Å | Atomic volume: | 71.07 | cm³/mol |
| Atomic radius: | 3.34 | Å | Ionic radius: | 1.74 (+1) | Å |
| Electronegativity: | 0.79 | Oxidation states: | |||
| 1st ionization pot.: | 3.8939 | V | 2nd ionization pot.: | 25.10 | V |
| 3rd ionization pot.: | -- | V | Specific heat: | 0.24 | J/gK |
| Heat of fusion: | 2.092 | kJ/mol | Heat of vapor.: | 67.740 | kJ/mol |
| Thermal conduct.: | 0.359 | W/cmK | Electrical conduct.: | 0.0489 | 10^6/cm ohm |
| Density: | 1.873 | g/cm³ | Valence: | 1 |