Element Astatine

Astatine ElementIt is a radioactive chemical element with the symbol At and atomic number 85.
Element Astatine is the rarest naturally occurring element in the Earth’s crust, occurring only as the decay product of various heavier elements.
All of astatine’s isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours. A sample of the pure element has never been assembled, because any macroscopic specimen would be immediately vaporized by the heat of its own radioactivity.
Most of the physical properties of astatine have been estimated (by interpolation or extrapolation), using theoretically or empirically derived methods.

Names and Identifiers

Chemical Formula:At
CAS:7440-68-8
Molecular Weight:210.00000g/mol
EC Number :n/a
MDL Number:n/a
Color:metallic/ Presumed very dark
Other Names:Astat, Astato
PubChem CID:5460479
IUPAC Name:Astatine
Inchl:InChI=1S/At
InChI Key:RYXHOMYVWAEKHL-UHFFFAOYSA-N
Canonical SMILES:[At]
ICSC Number:n/a

Physical & Chemical Properties

Phase:Solid
Density:6.35±0.15 g/cm³
Boiling Point:503±3 K ​(230±3 °C, ​445±5 °F)
Melting Point:n/a
Molecular Formula:At
Flash Point:n/a
Exact Mass:209.98700

There are 39 known isotopes of astatine, with atomic masses (mass numbers) of 191–229. Theoretical modeling suggests that 37 more isotopes could exist. No stable or long-lived astatine isotope has been observed, nor is one expected to exist.

Radiosotope data

IsotopeMass/DaHalf-lifeMode of decayNuclear spinNuclear magnetic moment
207At206.985781.81 hEC to 207Po; α to 203Bi9/2
208At207.986571.63 hEC to 208Po; α to 204Bi6
209At208.986165.4 hEC to 209Po; α to 205Bi6
210At209.987126 (12)8.1 hEC to 210Po; α to 206Bi5
211At210.987487.21 hEC to 211Po; α to 207Bi9/2

We’re ready to partner with you.