Pr
Lanthanide
Praseodymium
Z 59A 141mass 140.91
Atomic model
tap a particleEvery nucleon is drawn individually — 59 protons and 82 neutrons packed into the nucleus, with 59 electrons on shells outside.
59+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.
59−1
Electrons
Sit outside the nucleus and decide the chemistry, not the element.
Element data
- Nucleons
- 141 (59 p + 82 n)
- Electron shells
- 2 · 8 · 18 · 21 · 8 · 2
- Valence shell
- 2 electrons
- Atomic mass
- 140.91 u
Stability
Praseodymium has no measured radioactive isotope in this lab — its nuclei are stable, so decay must be shown as an illustration.
Open the decay lab