48 - Cadmium transition metal
Discovered by Karl Hermann in 1817
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.
Periodic table
| Shell | Electrons | Orbitals |
|---|---|---|
| 1 | 2 | 2 in 1s |
| 2 | 8 | 2 in 2s + 6 in 2p |
| 3 | 18 | 2 in 3s + 6 in 3p + 10 in 3d |
| 4 | 18 | 2 in 4s + 6 in 4p + 10 in 4d |
| 5 | 2 | 2 in 5s |
Electron shells
silvery bluish-gray metallic Appearance
112 u Atomic Mass
1.55 Å Atomic Radius
1.04k K Boiling Point
12 Group
2 Common Oxidation States
1.44 Å Covalent Radius
8.65 g/cm³ Density
−68 kJ/mol Electron Affinity
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 Electron Configuration
[Kr] 4d10 5s2 Electron Configuration (semantic)
1.69 Electronegativity
48 Electrons
8.99 eV First Ionization Energy
2 ICSD Oxidation States
867.8, 1631.4, 3616 kJ/mol Ionization Energies
594 K Melting Point
75 Mendeleev Number
26 J/(mol·K) Molar Heat
5 Number of Shells
64 Neutrons
48 Atomic Number
22 Number of Isotopes
1, 2 Oxidation States
5 Period
Solid Phase
48 Protons
2, 8, 18, 18, 2 Electron Shell Occupations