Answer:
The energy levels are: 3s and 3p
Explanation:
The sodium (Na) element, with atomic number 11 (number of protons: Z=11), has the next electronic configuration:
Z=11: 1s² 2s² 2p⁶ 3s¹ = [Ne] 3s¹
Hence, the electricity used in a sodium vapor lamp will excite the electron of the energy state n=3 from the s-orbital to the next highest energy p-orbital which then drops back to the lower energy s-orbital by the emission of a photon resulting in the production of light.
The transition of the electron is:
Excitation: [Ne] 3s¹ → [Ne] 3s⁰ 3p¹
Emission: [Ne] 3p¹ → [Ne] 3s¹
So, the energy levels that are involved in the process are 3s and 3p.
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