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Pronunciation | (KAD-mee-əm) |
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Appearance | silvery bluish-gray metallic |
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| 112.414(4)[1] |
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Group | group 12 |
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Period | period 5 |
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Block | d-block |
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Electron configuration | [Kr] 4d10 5s2 |
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Electrons per shell | 2, 8, 18, 18, 2 |
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Phase at STP | solid |
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Melting point | 594.22 K (321.07 °C, 609.93 °F) |
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Boiling point | 1040 K (767 °C, 1413 °F) |
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Density (near r.t.) | 8.65 g/cm3 |
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when liquid (at m.p.) | 7.996 g/cm3 |
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Heat of fusion | 6.21 kJ/mol |
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Heat of vaporization | 99.87 kJ/mol |
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Molar heat capacity | 26.020 J/(mol·K) |
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Vapor pressure
P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
at T (K) |
530 |
583 |
654 |
745 |
867 |
1040 |
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Oxidation states | −2, +1, +2 (a mildly basic oxide) |
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Electronegativity | Pauling scale: 1.69 |
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Ionization energies | - 1st: 867.8 kJ/mol
- 2nd: 1631.4 kJ/mol
- 3rd: 3616 kJ/mol
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Atomic radius | empirical: 151 pm |
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Covalent radius | 144±9 pm |
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Van der Waals radius | 158 pm |
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Spectral lines of cadmium |
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Natural occurrence | primordial |
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Crystal structure | hexagonal close-packed (hcp) |
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Speed of sound thin rod | 2310 m/s (at 20 °C) |
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Thermal expansion | 30.8 µm/(m⋅K) (at 25 °C) |
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Thermal conductivity | 96.6 W/(m⋅K) |
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Electrical resistivity | 72.7 nΩ⋅m (at 22 °C) |
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Magnetic ordering | diamagnetic[2] |
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Molar magnetic susceptibility | −19.8·10−6 cm3/mol[3] |
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Young's modulus | 50 GPa |
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Shear modulus | 19 GPa |
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Bulk modulus | 42 GPa |
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Poisson ratio | 0.30 |
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Mohs hardness | 2.0 |
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Brinell hardness | 203–220 MPa |
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CAS Number | 7440-43-9 |
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Discovery and first isolation | Karl Samuel Leberecht Hermann and Friedrich Stromeyer (1817) |
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Named by | Friedrich Stromeyer (1817) |
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Main isotopes[4] |
Decay |
|
abundance |
half-life (t1/2) |
mode |
product |
106Cd |
1.25% |
stable |
107Cd |
synth |
6.5 h |
ε |
107Ag |
108Cd |
0.89% |
stable |
109Cd |
synth |
462.6 d |
ε |
109Ag |
110Cd |
12.5% |
stable |
111Cd |
12.8% |
stable |
112Cd |
24.1% |
stable |
113Cd |
12.2% |
7.7×1015 y |
β− |
113In |
113mCd |
synth |
14.1 y |
β− |
113In |
IT |
113Cd |
114Cd |
28.8% |
stable |
115Cd |
synth |
53.46 h |
β− |
115In |
116Cd |
7.51% |
3.1×1019 y |
β−β− |
116Sn |
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Category: Cadmium | references |