84
209.00
Po
Polonium
Identification
CAS Number: 7440-08-6
Discovery Year: 1898
Discoverer: Pierre and Marie Curie
Discovery Location: France
Properties
Atomic Dimensions
Atomic Radius: 190 pm →
Atomic Radius (Rahm): 250 pm
Covalent Radius: 140 pm →Van der Waals Radius: 197 pm
Atomic Volume: 22.7 cm³/mol
Lattice Constant: 3.35 Å
Thermodynamics
Electronic Structure
Electron Config: [Xe] 4f14 5d10 6s2 6p4
Block: p
Period: 6 →Group: 16 →Electronegativity: 2 →Electron Affinity: 1.9 eV →Oxidation States: +2, +4, +6
Abundance & Geochemistry
Crust Abundance: 2e-10 mg/kg
Sea Abundance: 1.5e-14 mg/L
Geochemical Class: U/Th decay series
Goldschmidt Class: synthetic
About
Rare radioactive metallic element, belongs to group 16 of the periodic table. Over 30 known isotopes exist, the most of all elements. Po-209 has a half-life of 103 years. Possible uses in heating spacecraft. Discovered by Marie Curie in 1898 in a sample of pitchblende.
Isotopes
Po-208 208 ☢ 2.90 a
Po-209 209 ☢ 102 a
Po-210 210 ☢ 138 d
