Cadmium
A soft, toxic metal once common in pigments and batteries.
Inside the Cadmium atom
Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Cadmium atom step by step.
Electron configuration
[Kr] 4d10 5s2
A neutral Cadmium atom has 48 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.
Shell distribution
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Physical & atomic properties
- State (room temp)
- Solid
- Melting point
- 594 K (321 °C)
- Boiling point
- 1040 K (767 °C)
- Density
- 8.69 g/cm³
- Electronegativity
- 1.69 Pauling
- Atomic radius
- 155 pm
- 1st ionization energy
- 868 kJ/mol
- Category
- Transition metals
Discovery & naming
- Discovered
- 1817
- Discovered by
- Friedrich Stromeyer
- Origin of name
- Latin 'cadmia', an old name for zinc ore.
Notable uses
Rechargeable batteries, pigments, and coatings.
Where Cadmium comes from
Several comparable sources
Both slow neutron capture in dying stars and rapid capture in explosive events contribute meaningfully.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 48
- Atomic mass
- 112.41
- Category
- Transition metals
- Group · Period
- 12 · 5
- Block
- d-block
- Shells
- 2 · 8 · 18 · 18 · 2