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 Not considering  the electronic  spin, the degeneracy  of the second excited state (n=3)  of H-atom is 9,  while the degeneracy of the second excited state of H^-   is

Answer:

Explanation:

 In one electron  (hydrogenic) system, all orbitals of a shell remains degenerate, hence in second excited state, the degeneracy of H-atom is nine

 In case of many electrons system, different orbitals of a shell are non-degenerate, Hence,