48
Cd
Cadmium
112.414
Cadmium (Cd)
Transition MetalGroup 12Period 5d-block-block
Cadmium 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.
Latin name: Cadmium
Atomic Number
48
Atomic Mass
112.414 g/mol
Phase (STP)
Solid
Electron Config.
[Kr] 4d¹⁰ 5s²
General
SymbolCd
Atomic Number48
Atomic Mass112.414 g/mol
CategoryTransition Metal
Group12
Period5
Blockd-block
Electron Configuration[Kr] 4d¹⁰ 5s²
Valence Electrons12
Colourbluish-white metallic
Appearancesilvery bluish-gray metallic
CAS NumberCAS7440-43-9
Physical Properties
Phase (STP)Solid
Density8.65 g/cm³
Melting Point321.07°C · 609.93°F · 594.22 K
Boiling Point766.85°C · 1412.33°F · 1040.00 K
Atomic Properties
Atomic Radius161 pm
Electronegativity1.69 Pauling
Ionization Energy868 kJ/mol
Oxidation States+2
Ion ChargeCd2+
Thermodynamic
Molar Heat26.02 J/(mol·K)
Crystal Structure
Crystal Structurehexagonal close-packed
Mechanical Properties
Mohs Hardness2
Abundance
In Universe0.00003%
In Sun0.00002%
In Earth's Crust0.00009999999999999999%
Discovery & History
Discovery Year1817
Discovered ByFriedrich Stromeyer
Country of DiscoveryGermany
Named ByIsotopes of cadmium
Isotopes of Cadmium
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| Cd-106 | 1.25% | Stable | — |
| Cd-108 | 0.89% | Stable | — |
| Cd-110 | 12.49% | Stable | — |
| Cd-111 | 12.8% | Stable | — |
| Cd-112 | 24.13% | Stable | — |
| Cd-113 | 12.22% | 7.7 × 10¹⁵ years | β⁻ |
| Cd-114 | 28.73% | Stable | — |
| Cd-116 | 7.49% | 3.1 × 10¹⁹ years | β⁻β⁻ |