Ce
Lanthanide
Cerium
Z 58A 140mass 140.12
Atomic model
tap a particleEvery nucleon is drawn individually — 58 protons and 82 neutrons packed into the nucleus, with 58 electrons on shells outside.
58+1
Protons
Set the element — change this and it becomes a different atom.
820
Neutrons
Change only these and you get a different isotope of the same element.
58−1
Electrons
Sit outside the nucleus and decide the chemistry, not the element.
Element data
- Nucleons
- 140 (58 p + 82 n)
- Electron shells
- 2 · 8 · 18 · 20 · 8 · 2
- Valence shell
- 2 electrons
- Atomic mass
- 140.12 u
Stability
Cerium has no measured radioactive isotope in this lab — its nuclei are stable, so decay must be shown as an illustration.
Open the decay lab