7.3 Electron Configurations
Atomic Orbitals (s, p, and d orbitals)
| Rules for Ground State Electron Configurations | |
|---|---|
| Aufbau Principle | Electrons fill the lowest energy orbitals first. |
| Hund’s Rule | Degenerate orbitals each get an electron before pairing. |
| Pauli Exclusion Principle | No 2 electrons in an atom have the same 4 quantum numbers. |
Standard and Noble Gas configurations
Exceptions (Cr, Mo and Cu, Ag, Au)
Ions (transition metals too)
Number of Valence Electrons
Ground State vs. Excited State