Pt
Transition metal
Platinum
Z 78A 195mass 195.08
Atomic model
tap a particleEvery nucleon is drawn individually — 78 protons and 117 neutrons packed into the nucleus, with 78 electrons on shells outside.
78+1
Protons
Set the element — change this and it becomes a different atom.
1170
Neutrons
Change only these and you get a different isotope of the same element.
78−1
Electrons
Sit outside the nucleus and decide the chemistry, not the element.
Element data
- Nucleons
- 195 (78 p + 117 n)
- Electron shells
- 2 · 8 · 18 · 32 · 16 · 2
- Valence shell
- 2 electrons
- Atomic mass
- 195.08 u
Stability
Platinum has no measured radioactive isotope in this lab — its nuclei are stable, so decay must be shown as an illustration.
Open the decay lab