Sr
Alkaline earth metal
Strontium
Z 38A 88mass 87.62
Slow-motion stage
Strontium-90
proton
neutron
electron (β⁻)
Parent nucleus · 90 nucleons
38 protons (coral) and 52 neutrons (blue) are packed together and held by the strong force.
A real decay takes about 10⁻²¹ s. At ⅓× this stage stretches it across eleven seconds.
Choose a reaction
Reaction
9038Sr9039Y+β⁻+ ν̄
A neutron turns into a proton. An electron and an antineutrino fly out.
Z
3839
+1
A
9090
no change
n⁰
5251
-1
Energy released
0.546MeV
Electron (max)0.546 MeV
Mass convertedE = Δm c²0.00059 u
In joules8.75 × 10-14 J
Compared with a bonda C–C bond is 3.6 eV≈ 151,667 ×
Half-life of Strontium-90
28.8 years
A fission product that behaves chemically like calcium.
The particle
- Charge
- −1
- Mass
- 1/1836 u
- Speed
- Up to 99.9% of the speed of light
- Ionising power
- Moderate
- Stopped by
- A few millimetres of aluminium