Ac

Actinium-221

Protons (Z)

89

Neutrons (N)

132

Mass number

221

Half-Life

52.0 ms

Abundance

---

Mass

221.016 u

Mass Excess

14,530.0 keV

Spin

(9/2-)

Discovered

1968

Binding energy per nucleon

7,691 keV

Neutron separation energy

7,285 keV

Proton separation energy

3,031 keV

Decay Mode

αFrancium-217100%

Decay chain

Actinium-221Z 89 · N 13252.0 ms
α100%
α100%
α100%
α100%