| Nobelium | ||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pronunciation | ||||||||||||||||||||||||||||||||||||||||||||||||
| Mass number | [259] | |||||||||||||||||||||||||||||||||||||||||||||||
| Nobelium in the periodic table | ||||||||||||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||
| Atomic number (Z) | 102 | |||||||||||||||||||||||||||||||||||||||||||||||
| Group | f-block groups (no number) | |||||||||||||||||||||||||||||||||||||||||||||||
| Period | period 7 | |||||||||||||||||||||||||||||||||||||||||||||||
| Block | f-block | |||||||||||||||||||||||||||||||||||||||||||||||
| Electron configuration | [Rn] 5f14 7s2 | |||||||||||||||||||||||||||||||||||||||||||||||
| Electrons per shell | 2, 8, 18, 32, 32, 8, 2 | |||||||||||||||||||||||||||||||||||||||||||||||
| Physical properties | ||||||||||||||||||||||||||||||||||||||||||||||||
| Phase at STP | solid (predicted)[1] | |||||||||||||||||||||||||||||||||||||||||||||||
| Melting point | 1100 K (800 °C, 1500 °F) (predicted)[1] | |||||||||||||||||||||||||||||||||||||||||||||||
| Density (near r.t.) | 9.9(4) g/cm3 (predicted)[2][a] | |||||||||||||||||||||||||||||||||||||||||||||||
| Atomic properties | ||||||||||||||||||||||||||||||||||||||||||||||||
| Oxidation states | common: +3 +2[3] | |||||||||||||||||||||||||||||||||||||||||||||||
| Electronegativity | Pauling scale: 1.3 (predicted)[4] | |||||||||||||||||||||||||||||||||||||||||||||||
| Ionization energies |
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| Other properties | ||||||||||||||||||||||||||||||||||||||||||||||||
| Natural occurrence | synthetic | |||||||||||||||||||||||||||||||||||||||||||||||
| Crystal structure | face-centered cubic (fcc) (predicted)[2] | |||||||||||||||||||||||||||||||||||||||||||||||
| CAS Number | 10028-14-5 | |||||||||||||||||||||||||||||||||||||||||||||||
| History | ||||||||||||||||||||||||||||||||||||||||||||||||
| Naming | after Alfred Nobel | |||||||||||||||||||||||||||||||||||||||||||||||
| Discovery | Joint Institute for Nuclear Research (1965) | |||||||||||||||||||||||||||||||||||||||||||||||
| Isotopes of nobelium | ||||||||||||||||||||||||||||||||||||||||||||||||
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Nobelium is a synthetic chemical element; it has symbol No and atomic number 102. It is named after Alfred Nobel, the inventor of dynamite and benefactor of science. A radioactive metal, it is the tenth transuranium element, the second transfermium, and is the penultimate member of the actinide series. Like all elements with atomic number over 100, nobelium can only be produced in particle accelerators by bombarding lighter elements with charged particles. A total of twelve nobelium isotopes are known to exist; the most stable is 259No with a half-life of 58 minutes, but the shorter-lived 255No (half-life 3.1 minutes) is most commonly used in chemistry because it can be produced on a larger scale.
Chemistry experiments have confirmed that nobelium behaves as a heavier homolog to ytterbium in the periodic table. The chemical properties of nobelium are not completely known: they are mostly only known in aqueous solution. Before nobelium's discovery, it was predicted that it would show a stable +2 oxidation state as well as the +3 state characteristic of the other actinides; these predictions were later confirmed, as the +2 state is much more stable than the +3 state in aqueous solution and it is difficult to keep nobelium in the +3 state.
In the 1950s and 1960s, many claims of the discovery of nobelium were made from laboratories in Sweden, the Soviet Union, and the United States. Although the Swedish scientists soon retracted their claims, the priority of the discovery and therefore the naming of the element was disputed between Soviet and American scientists. It was not until 1992 that the International Union of Pure and Applied Chemistry (IUPAC) credited the Soviet team with the discovery. Even so, nobelium, the Swedish proposal, was retained as the name of the element due to its long-standing use in the literature.
- ^ a b Lide, David R., ed. (2003). CRC Handbook of Chemistry and Physics (84th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0484-9.
- ^ a b Fournier, Jean-Marc (1976). "Bonding and the electronic structure of the actinide metals". Journal of Physics and Chemistry of Solids. 37 (2): 235–244. Bibcode:1976JPCS...37..235F. doi:10.1016/0022-3697(76)90167-0.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 28. ISBN 978-0-08-037941-8.
- ^ Dean, John A., ed. (1999). Lange's Handbook of Chemistry (15 ed.). McGraw-Hill. Section 4; Table 4.5, Electronegativities of the Elements.
- ^ Sato, Tetsuya K.; Asai, Masato; Borschevsky, Anastasia; Beerwerth, Randolf; Kaneya, Yusuke; Makii, Hiroyuki; Mitsukai, Akina; Nagame, Yuichiro; Osa, Akihiko; Toyoshima, Atsushi; Tsukada, Kazuki; Sakama, Minoru; Takeda, Shinsaku; Ooe, Kazuhiro; Sato, Daisuke; Shigekawa, Yudai; Ichikawa, Shin-ichi; Düllmann, Christoph E.; Grund, Jessica; Renisch, Dennis; Kratz, Jens V.; Schädel, Matthias; Eliav, Ephraim; Kaldor, Uzi; Fritzsche, Stephan; Stora, Thierry (25 October 2018). "First Ionization Potentials of Fm, Md, No, and Lr: Verification of Filling-Up of 5f Electrons and Confirmation of the Actinide Series". Journal of the American Chemical Society. 140 (44): 14609–14613. doi:10.1021/jacs.8b09068.
- ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
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