Why do the 3s, 3p and 3d orbitals have the same energy in a hydrogen atom

The correct answer is (d) 3s orbital is lower in energy than 3p orbital

In a hydrogen atom, 3s,3p and 3d orbitals will have same energy. In hydrogen atom all orbitals belong to the same shell have same energy in hydrogen atom.

Solution

Energy of Orbital in Hydrogen (single-electron atom)

• The exception to the general behaviour of the energy of orbitals as explained above is observed in Hydrogen, the energy of orbital is only dependent on principal quantum number, and so the 2s and 2p orbital in hydrogen atom have the same energy.
• The 1s orbital in hydrogen atom corresponds to the most stable condition and is called ground state whereas any other orbital afterwards has higher energy than that of 1s orbital and are called excited state.