85At
Element 85
Astatine
Halogens
Astatine is a very rare radioactive chemical element with the chemical symbol At and atomic number 85.
Key data
- Atomic number
- 85
- Atomic mass
- 210.000 u
- Group / Period
- 17 / 6
- Block
- p-block
- Phase at STP
- Solid
- Density
- 6.35 g/cm³
- Melting point
- 301.9 °C
- Boiling point
- 336.9 °C
- Electron configuration
- [Xe] 4f14 5d10 6s2 6p5
Common uses
- •Cancer therapy research
- •Rarest natural element
- •Very short half-life
Discovery
Year: 1940
Discovered by: Dale R. Corson
Frequently asked questions
What is the atomic number of Astatine?
Astatine has atomic number 85. Its symbol is At and its atomic mass is 210 u.
What category of element is Astatine?
Astatine is classified as halogens. It sits in group 17, period 6 of the periodic table.
What is Astatine used for?
Common uses of Astatine include: Cancer therapy research, Rarest natural element, Very short half-life.
When was Astatine discovered?
Astatine was discovered in 1940 by Dale R. Corson.
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