Astatine
Reactive Nonmetal
Astatine (At) is a chemical element with atomic number 85, classified as a reactive nonmetal. At room temperature it is a solid. It was discovered in 1940 by Dale R. Corson et al..
Properties
- Atomic number
- 85
- Atomic mass
- 210 u
- Category
- Reactive Nonmetal
- Group
- 17
- Period
- 6
- Block
- p-block
- Electron configuration
- [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁵
- Phase at STP
- Solid
- Density
- 7 g/cm³
- Melting point
- 575 K (301.9 °C)
- Boiling point
- 610 K (336.9 °C)
- Electronegativity
- 2.2
- Atomic radius
- 127 pm
- Ionization energy
- 9.318 eV
- Discovery
- 1940 · Dale R. Corson et al.
Common uses
Cancer treatment research, radioactive tracers
Did you know?
Rarest naturally occurring element - less than 1 ounce exists on Earth.