Astatine Element: General Properties and its Uses

Explore Astatine Element (At), the rarest naturally occurring element and heaviest halogen. Highly radioactive with short half-lives (e.g., At-210 at 8.1 hours), it's primarily used in targeted alpha therapy for cancer research, showcasing its unique properties despite its extreme scarcity.

Context: The University of Jyväskylä in Finland has recently detected and successfully measured the half-life of the heaviest known proton-emitting isotope of astatine, ¹⁸⁸At.

About Astatine Element

General Properties

Symbol & Atomic Number: At, atomic number 85
Category: Halogen group (Group 17)
Appearance: Likely a dark-colored solid at room temperature and pressure
Radioactivity: Highly radioactive; emits a blue glow due to ionising the surrounding air
Isotopes: 41 known radioactive isotopes, ranging from mass numbers 188 and 190 to 229

Chemical & Physical Properties

Chemical Behaviour: Resembles iodine but exhibits more metallic characteristics
Compounds: Forms compounds similar to iodine but with more metallic properties
Electronegativity: Estimated to be between 2.2 and 2.5
Density: Estimated to be around 6.3 g/cm³
Melting Point: Estimated to be between 302°C and 337°C
Boiling Point: Estimated to be between 337°C and 352°C

Uses

Medical Applications: Used in targeted alpha-particle cancer therapy
- Astatine is released in the human thyroid; hence, it is used in the treatment of thyroid diseases.
Research: Studied for potential use in radiopharmaceuticals
Industrial Applications: Limited due to its rarity and radioactivity