Ra
Radium-221
Protons (Z)
88
Neutrons (N)
133
Mass number
221
Half-Life
25.0 s
Abundance
---
Mass
221.014 u
Mass Excess
12,964.0 keV
Spin
5/2+
Discovered
1949
Binding energy per nucleon
7,701 keV
Neutron separation energy
5,379 keV
Proton separation energy
5,807 keV
Decay Mode
Decay chain
- RaRadium-221Z 88 · N 13325.0 s
- α~100%
- α100%
- α100%
- β⁻100%
- α100%