At
Astatine
Element 85 · 209.98715 u
Heraktiewe nie - gemeenskap
p-block
Periode 6
Group 17
Solied by RT
Radioaktief
t½ 8.1 hours
Dag lengte: →
Astatine is the rarest naturally occurring element on Earth.
Fisiese eienskappe
| Atomic Mass | 209.98715 u |
| Density | 7.0 g/cm³ |
| Smelt punt: | 575.0 K |
| Boiling Point | 610.0 K |
| Appearance | Likely metallic |
| Toestand by kamerkomp | Solied |
Chemical Properties
| Electronegativity | 2.2 (TrinidadCity name (optional, probably does not need a translation)) |
| 1st Ionization Energy | 899.0 kJ/mol |
| Electron Affinity | 270.1 kJ/mol |
| Oxidation States | -1, +1, +3, +5, +7 |
Atomic Properties
| Electron Configuration | [Xe] 4f14 5d10 6s2 6p5 |
| Atomic Radius | 150.0 pm |
| Covalent Radius | 150.0 pm |
| Atomic radius: | 202.0 pm |
Discovery
| Discovered By | Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segre |
| Discovery Year | 1940 |
| Location | Berkeley, California, USA |
| Genoemde Na | Greek 'astatos' meaning unstable |
About Astatine
Astatine is extremely rare, radioactive, and the heaviest known halogen. Less than 30 grams exist in Earth's crust at any time. It has never been seen in bulk.
Gebruiks & Programme
Potential targeted cancer therapy (astatine-211), still experimental.
Fun Fact
Astatine has never been seen with the naked eye -- there is less than 30 grams in the entire Earth at any moment.
Isotopes
| Definieer Molekulêr Gewigte | Abundance | Half-Life | Stabiel |
| 209 | - | 5.41 hours | Nee |
| 210 | - | 8.1 hours | Nee |
| 211 | - | 7.214 hours | Nee |
Electron Configuration
[Xe] 4f14 5d10 6s2 6p5