Elements / 85
85At[210]
Astatine
Halogen · p-block · ring P · spoke 17
Astatine is element 85, a halogen. It sits on ring P (period 6) on spoke 17, the halogens. Follow that spoke toward the center and out again to find its chemical relatives.
Properties
| Density | 6.35 g/cm³ | Terrain → |
|---|---|---|
| Melting point | 575 K · 302 °C | Terrain → |
| Boiling point | 610 K · 337 °C | Terrain → |
| Electronegativity | 2.20 | Terrain → |
| First ionization energy | 899 kJ/mol | Terrain → |
| Atomic weight | 210 u | Terrain → |
| Crustal abundance | 3.0 × 10⁻²⁷ ppm | Terrain → |
| Discovered | 1940 | Terrain → |
Values from open reference data; see sources. "Terrain" opens that property as a 3D landscape across the whole spiral.
Two things you might not know
- No one has ever seen a solid sample: a visible piece would vaporize itself from the heat of its own radioactivity.
- The rarest naturally occurring element in Earth's crust, first made at Berkeley in 1940. Its name means unstable.
Checked against en.wikipedia.org.
Spoke 17: Halogens
Ring P (period 6)
Play with Astatine
Watch it fly into its seat, or raise the whole spiral into a landscape and see where it peaks.