Polonium (Po)
Polonium is the chemical element with atomic number 84 and symbol Po. It is a post-transition metal in period 6, group 16, with a standard atomic weight of 209 u.
Key facts
- Z
- 84
- Atomic weight
- 209 u no stable isotope
- Category
- post-transition metal
- State at 298 K
- Solid
- Occurrence
- from decay, radioactive
- Discovered
- 1898
- CAS
- 7440-08-6
Measured properties
| Property | Value | Source |
|---|---|---|
| Electronegativity | 2 | National Center for Biotechnology Information (NIH) |
| Melting point | 527 K | National Center for Biotechnology Information (NIH) |
| Boiling point | 1,235 K | National Center for Biotechnology Information (NIH) |
| Density stp | 9.32 g/cm³ | National Center for Biotechnology Information (NIH) |
| Atomic radius empirical | 197 pm | National Center for Biotechnology Information (NIH) |
| Ionization energy 1st | 812.1 kJ/mol | National Center for Biotechnology Information (NIH) |
| Electron affinity | 183.3 kJ/mol | National Center for Biotechnology Information (NIH) |
Electron configuration
- Noble gas notation
- [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁴
- Full notation
- 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁴
- Electrons per shell
- 2, 8, 18, 32, 18, 6