From Wikipedia, the free encyclopediaRutherfordium is a chemical element with symbol Rf and atomic number 104, named in honor of physicist Ernest Rutherford. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 267Rf, has a half-life of approximately 1.3 hours. In the periodic table of the elements, it is a d - block element and the second of the fourth - row transition elements. | |||||||||
Rutherfordium in the periodic table | |||||||||
---|---|---|---|---|---|---|---|---|---|
Symbol | Rf | ||||||||
Atomic number | 104 | ||||||||
Group | 4 | ||||||||
Period | 7 | ||||||||
Block | d | ||||||||
Element category | Transition Metal | ||||||||
Physical properties | |||||||||
Phase at STP | Solid | ||||||||
Density | 23.2 g/cm3 | ||||||||
Atomic weight | 267 u | ||||||||
Melting point | 2400 K 2126.85 °C 3860.33 °F | ||||||||
Boiling point | 5800 K 5526.85 °C 9980.33 °F | ||||||||
Atomic properties | |||||||||
Electronegativity (Pauling Scale) | |||||||||
Electron affinity | kJ/mol | ||||||||
Oxidation states | (+2), (+3), +4 () | ||||||||
Ionization energies |
| ||||||||
Electron configuration | |||||||||
Elektronkonfiguration (shorthand) | [Rn] 5f14 6d2 7s2 | ||||||||
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f14 6s2 6p6 6d2 7s2 | ||||||||
Electrons per shell | 2, 8, 18, 32, 32, 10, 2 | ||||||||
History | |||||||||
Discovered | 1969 | ||||||||
Discovered by | Joint Institute for Nuclear Research |