Question

If energy in h atom is -r/9 the degeneracy of this h atom is

Answer 1

There are the following orbitals in the n=3 energy level.

one s

three p

five d

For a total of 9 orbitals. in a single electron species like hydrogen, they would all be degenerate (exactly the same energy). Their degeneracy is only split in multi-electron atoms, where inner electrons shield the core from the outer electrons. since s better at penetrating the shielding than p, which in turn is better at penetrating than d, in multi electron atoms, s is lower energy than p, which is lower energy than d.

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