Periodic table

Helium-3 (He-3)

Identity

Protons
2
Neutrons
1
Mass number
3
Mass
3.016029 ± 0.000060 u
Mass excess
14.931 MeV
Spin
1/2+*

Stability

stable

Natural occurrence

0.000200 % of helium

Produced by

All isotopes of helium