Neptunium-235 (Np-235)

Identity

Protons

93

Neutrons

142

Mass number

235

Mass

235.0 ± 1.5 u

Mass excess

41.043 MeV

Spin

5/2+

Stability

Half-life: 1.08 years

Natural occurrence

Not found in nature

Decays to

• electron capture 100.0 % → U-235
• alpha 0.0026 % → Pa-231