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Astatine - At General Information Discovery Astatine was synthesised in 1940 by D.R. Corson, K.R. MacKenzie and F. Serge in California, USA, by bombarding bismuth with alpha particles. Source Astatine can be obtained in various ways, but not in weighable amounts. The usual method of preparation is neutron bombardment of 200Bi to produce 211At. Biological Role Astatine has no known biological role. It is toxic due to its radioactivity. General Information The mass spectrometer has been used to confirm that this highly radioactive halogen behaves chemically like other halogens, particularly iodine. |
| Physical Information | |||
| Atomic Number | 85 | ||
| Relative Atomic Mass (12C=12.000) | 210 (radioactive) | ||
| Melting Point/K | 575 | ||
| Boiling Point/K | 610 | ||
| Ground State Electron Configuration | [Xe]4f145d106s26p5 | ||
| Electron Affinity(M-M-)/kJ mol-1 | -256 |
| Key Isotopes | ||||||
| nuclide | 210At | 211At | ||||
| atomic mass | 210.99 | |||||
| natural abundance | 0% | 0% | ||||
| half-life | 8.3 h | 7.21 h |
| Other Information | ||
| Enthalpy of Fusion/kJ mol-1 | 23.8 | |
| Oxidation States | ||
| At-1, At+1, At+3 | ||
| Covalent Bonds /kJ mol-1 | ||
| At - At | 110 | |
| Ionisation Energies/kJ mol-1 | ||
| M - M+ | 930 | |
| M+ - M2+ | 1600 | |
| M2+ - M3+ | 2900 | |
| M3+ - M4+ | 4000 | |
| M4+ - M5+ | 4900 | |
| M5+ - M6+ | 7500 | |
| M6+ - M7+ | 8800 | |
| M7+ - M8+ | 13300 | |
| M8+ - M9+ | 15400 | |
| M9+ - M10+ | 17700 | |
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