Polonium (symbol Po, atomic number 84) is an intensely radioactive metalloid, infamous as a poison. It is classified as a post-transition metal and sits in group 16, period 6 of the periodic table.
Overview
Polonium is the chemical element with atomic number 84 and the symbol Po. With a standard atomic weight of [209], it is a post-transition metal. In the periodic table it occupies group 16 and period 6, and under standard conditions it is normally a solid. Polonium is an intensely radioactive metalloid, infamous as a poison.
Atomic structure
An atom of Polonium has 84 protons in its nucleus and, when neutral, 84 electrons arranged in the configuration [Xe] 4f14 5d10 6s2 6p4. Polonium has no stable isotope; the value [209] refers to the mass number of its most stable or most commonly produced isotope.
Discovery and place in the table
Polonium was discovered in 1898 by Marie Curie, Pierre Curie. It follows Bismuth (Bi) and precedes Astatine (At) in order of atomic number.
| Atomic number | 84 |
|---|---|
| Symbol | Po |
| Atomic mass | [209] |
| Category | Post-transition metal |
| Group | 16 |
| Period | 6 |
| Electron configuration | [Xe] 4f14 5d10 6s2 6p4 |
| Phase at STP | Solid |
| Discovered | 1898 (Marie Curie, Pierre Curie) |