From Wikipedia, the free encyclopediaCadmium is a chemical element with symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it prefers oxidation state +2 in most of its compounds and like mercury it shows a low melting point compared to transition metals. | |||||||
Cadmium in the periodic table | |||||||
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Symbol | Cd | ||||||
Atomic number | 48 | ||||||
Group | 12 | ||||||
Period | 5 | ||||||
Block | d | ||||||
Element category | Transition Metal | ||||||
Physical properties | |||||||
Phase at STP | Solid | ||||||
Density | 8.65 g/cm3 | ||||||
Atomic weight | 112.414 u | ||||||
Melting point | 594.22 K 321.07 °C 609.926 °F | ||||||
Boiling point | 1040 K 766.85 °C 1412.33 °F | ||||||
Atomic properties | |||||||
Electronegativity (Pauling Scale) | 1.69 | ||||||
Electron affinity | -68 kJ/mol | ||||||
Oxidation states | −2, +1, +2 (a mildly basic oxide) | ||||||
Ionization energies |
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Electron configuration | |||||||
Elektronkonfiguration (shorthand) | [Kr] 4d10 5s2 | ||||||
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 | ||||||
Electrons per shell | 2, 8, 18, 18, 2 | ||||||
History | |||||||
Discovered | 1817 | ||||||
Discovered by | Karl Samuel Leberecht Hermann Friedrich Stromeyer Karl Samuel Leberecht Hermann | ||||||
Named by | Isotopes of cadmium |