Ruthenium-99 (Ru-99)

Identity

Protons

44

Neutrons

55

Mass number

99

Mass

98.91 ± 0.37 u

Mass excess

-87.625 MeV

Spin

5/2+*

Stability

stable

Natural occurrence

12.76 % of ruthenium

Produced by

• Tc-99
• Rh-99