Astatine
Astatine is the rarest naturally occurring element in Earth's crust, with less than 25 grams estimated to exist at any given time. It's highly radioactive, with its most stable isotope having a half-life of only 8.1 hours. As a halogen, astatine has chemical properties similar to iodine, though it's more metallic. Due to its extreme rarity and radioactivity, research on astatine is difficult, and it has no significant applications outside of basic research.
Physical and Chemical Properties
Basic Properties
Physical Properties
Electronic Properties
Historical
Interactive Atomic Model
Electron Shells Visualization
This visualization shows the Bohr model of the atom, with electrons arranged in concentric shells (energy levels) around the nucleus. Each shell can hold a specific maximum number of electrons (2, 8, 18, 32...) following the 2n² rule. Electrons fill inner shells before occupying outer shells.
The blue circles represent electrons orbiting the nucleus (shown in the center). This simplified model effectively demonstrates electron distribution but doesn't accurately represent the quantum mechanical nature of electrons.
Click the buttons above to switch between different visualization modes.
Fascinating Facts
- Astatine is the rarest naturally occurring element on Earth, with less than 1 gram present in Earth's crust at any time.
- Its name comes from the Greek word 'astatos,' meaning 'unstable.'
- Even if you had a visible amount of astatine, it would immediately vaporize itself due to the heat from its own radioactivity.
- Scientists have never been able to collect enough astatine to see it with the naked eye.
- It's estimated that the total amount ever produced in laboratories is less than 1 microgram.
Applications and Uses
Research in radiochemistry
Potential applications in targeted alpha therapy for cancer (under research)
Production of other radioactive isotopes
Studies of halogen chemical properties
Training for handling radioactive materials
Historical Timeline
Discovery
Astatine was discovered by Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè in 1940.
Modern Applications
Astatine is now used in various applications including Research in radiochemistry and Potential applications in targeted alpha therapy for cancer (under research).