084Post-transition metal · Group 16 · Period 6
Polonium
Polonium (Po) is element 84, a post-transition metal in the p-block — group 16, period 6. It is a solid at room temperature with 6 electron shells (2, 8, 18, 32, 18, 6) and an atomic mass of 209 u.
- Atomic mass
- 209.0 u
- Phase · STP
- solid
- Melting
- 527 K · 254 °C
- Boiling
- 1235 K · 962 °C
- Electronegativity
- 2
- Density
- 9.196 g/cm³
Photograph — Chemical ELements A Virtual Museum, CC BY 3.0 <https://creativecommons.org/licenses/by/3.0> source: https://images-of-elements.com/polonium.php
Identity
- Atomic number
- 84
- Standard atomic weight
- 209.0 u
- Category
- Post-transition metal
- Group
- 16 · Chalcogens
- Period
- 6
- Block
- p-block
- Oxidation states
- +4, +2
Physical properties
- Melting point
- 527 K · 254 °C
- Boiling point
- 1235 K · 962 °C
- Density
- 9.196 g/cm³
- Molar heat capacity
- 26.4 J/(mol·K)
- Atomic radius
- 197 pm
- Electron affinity
- 136 kJ/mol
Atomic structure
84protons
125neutrons
84electrons
6valence e⁻
- Noble-gas notation
- [Xe] 4f14 5d10 6s2 6p4
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p4
- Electrons per shell
- 2, 8, 18, 32, 18, 6
Periodic trends
Where Polonium ranks across all 118 elements.
Discovery
- Discovered
- 1898
- Discovered by
- Pierre Curie
- Named by
- —
- Appearance
- silvery