What is the sequence of energies of 3s, 3p and 3d-orbitals in
(i) a hydrogen atom, and
(ii) a multielectron atom?

Explanation

To determine the sequence of energies of the 3s, 3p, and 3d orbitals in both a hydrogen atom and a multielectron atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Energy Levels in Hydrogen Atom:**
- In a hydrogen atom, there is only one electron. Therefore, the energy levels of the orbitals depend solely on the principal quantum number (n).
- For the orbitals 3s, 3p, and 3d, they all have the same principal quantum number (n = 3).
- Since they have the same n value, the 3s, 3p, and 3d orbitals are degenerate, meaning they have the same energy.
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