What is the orbital box diagram for the valence electrons of a phosphorus atom?

Okay, here's the orbital box diagram for the valence electrons of a phosphorus atom (atomic number 15): **Phosphorus (P): 1s² 2s² 2p⁶ 3s² 3p³** Valence electrons are in the 3s and 3p subshells. ``` 3s 3p [ ↑↓ ] [ ↑ ] [ ↑ ] [ ↑ ] ``` **Explanation:** * **3s orbital:** It has two electrons with opposite spins (Pauli Exclusion Principle). * **3p orbitals:** It has three electrons. According to Hund's rule, these three electrons occupy each of the three p-orbitals (px, py, pz) singly with parallel spins before any pairing occurs.