PERIODIC ELEMENT
Cs (Cesium)
| Atomic number | : | 55 |
| Atomic mass | : | 132.9054 g.mol-1 |
| Electronegativity according to Pauling | : | 0.7 |
| Density | : | 1.9 g.cm-3 at 20 °C |
| Melting point | : | 28.4 °C |
| Boiling point | : | 669 °C |
| Vanderwaals radius | : | 0.267 nm |
| Ionic radius | : | 0.167 nm |
| Isotopes | : | 12 |
| Electronic shell | : | [Xe] 6s1 |
| Energy of first ionisation | : | 375.6 kJ.mol-1 |
| Discovered by | : | Fustov Kirchhoff in 1860 |
| Atomic Structure | Uses (removes air traces in vacuum tubes) | |