F

Fluorine-21

Protons (Z)

9

Neutrons (N)

12

Mass number

21

Half-Life

4.16 s

Abundance

---

Mass

21.0 u

Mass Excess

-47.6 keV

Spin

5/2+

Discovered

1955

Binding energy per nucleon

7,738 keV

Neutron separation energy

8,101 keV

Proton separation energy

11,133 keV

Decay Mode

β⁻Neon-21100%

Decay chain

Fluorine-21Z 9 · N 124.16 s
β⁻100%