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 Protactinium (Pa)
Protactinium (Pa) 
















 
 
 
Isotope Mass Abundance Spin Mag Moment
231Pa 231.035880 Trace 3/2 +2.01 234Pa 234.043303 Trace 4
 
Pa I  Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p65f26d7s2  4K11/2
      Ionization energy  47500 cm-1 (5.89 eV)   Ref. S74
 
Pa II Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p65f27s2  3H4