Periodic table / Transition metals

48Cadmium

Cadmium is a transition metal in group 12, period 5. At 25 °C it is a solid.

Cd
Shells: 2, 8, 18, 18, 2. A simple picture: electrons do not move in circles.
Symbol
Cd
Atomic number
48 protons in the nucleus
Standard atomic weight
112.41 ± 0.01Some geological samples have an unusual isotope mix, so their atomic weight can fall outside this range.
Electron configuration
[Kr] 4d10 5s2
Electrons in each shell
2, 8, 18, 18, 2
Group, period, block
12, 5, d
Family
Transition metals
State at 25 °C
solid
Electronegativity
1.69 (Pauling scale)
First ionisation energy
867.8 kJ/mol (8.99382 eV)
Where these numbers come from

Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.