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Periodic table
›
selenium
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Se-78
Selenium-78 (Se-78)
Identity
Protons
34
Neutrons
44
Mass number
78
Mass
77.92 ± 0.19 u
Mass excess
-77.026 MeV
Spin
0+
Stability
stable
Natural occurrence
23.69 %
of selenium
All isotopes of selenium