Atomic Weights and Isotopic Compositions for Selenium
 Isotope   Relative
Atomic Mass
 
   Isotopic
  Composition  
Standard
Atomic Weight
 
 Notes 
 
34 Se 74   73.922 475 934(15)   0.0089(4)    78.971(8) r
76   75.919 213 704(17)   0.0937(29)
77   76.919 914 154(67)   0.0763(16)
78   77.917 309 28(20)   0.2377(28)
80   79.916 5218(13)   0.4961(41)
82   81.916 6995(15)   0.0873(22)

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