|  | 
| Classifications
 |  | Alternate Names | None |  | Names of Allotropes | None |  | Block | p |  | Group | 17 |  | Period | 6 |  | Series | Halogen |  | Electron Configuration | [Xe]6s24f145d106p5 |  | Color | Silver |  | Discovery | | 1940 in The  United  States | 
 |  | Gas phase | N/A |  | CAS Number | CAS7440-68-8 |  | CID Number | N/A |  | RTECS Number | N/A |  | Electrical properties
 |  | Electrical Type | N/A |  | Electrical Conductivity | N/A |  | Resistivity | N/A |  | Superconducting Point | N/A |  | Magnetic properties
 |  | Magnetic Type | N/A |  | Curie Point | N/A |  | Mass Magnetic Susceptibility | N/A |  | Molar Magnetic Susceptibility | N/A |  | Volume Magnetic Susceptibility | N/A |  | Abundances
 |  | % in Universe | N/A |  | % in Sun | N/A |  | % in Meteorites | 0% |  | % in Earth's Crust | 0% |  | % in Oceans | 0% |  | % in Humans | 0% |  | Atomic dimensions and structure
 |  | Atomic Radius | 127 pm |  | Covalent Radius | 150 pm |  | Van der Waals Radius | N/A |  | Crystal Structure | N/A |  | Lattice Angles | N/A |  | Lattice Constants | N/A |  | Space Group Name | N/A |  | Space Group Number | N/A |  | Nuclear Properties
 |  | Half-Life | 8.055555555556 h |  | Lifetime | 11.66666666667 h |  | Decay Mode | BetaPlusDecay |  | Quantum Numbers | 2P3/2 |  | Neutron Cross Section | N/A |  | Neutron Mass Absorption | N/A |  | Known Isotopes | | 193At, 194At, 195At, 196At, 197At, 198At, 199At, 200At, 201At, 202At, 203At, 204At, 205At, 206At, 207At, 208At, 209At, 210At, 211At, 212At, 213At, 214At, 215At, 216At, 217At, 218At, 219At, 220At, 221At, 222At, 223At | 
 |  | Stable Isotopes |  |  | Isotopic Abundances |  |  |