CHEM 200 Chapter Notes - Chapter 8: Electron Configuration, Atomic Orbital, Isoelectronicity
Document Summary
Chapter 8 electron configuration and chemical periodicity. Three additional features become important in many-electron atoms: a fourth quantum number, a limit on the number of electrons in an orbital, a splitting of energy levels into sublevels. The exclusion principle: exclusion principle no two electrons in the same atom can have the same four quantum numbers, an atomic orbital can hold a maximum of two electrons and they must have opposing spins. Higher charges interact more strongly than lower charges. A higher nuclear charge increases nucleus-electron attractions and, thus, lowers sublevel energy (stabilizes the atom): shielding: the effect of electron repulsions on sublevel energy. Repulsions counteract the nuclear attraction somewhat, making each electron easier to remove by, in effect, helping to push it away experiences, and this lower nuclear charge makes the electron easier to remove. Shielding reduces the full nuclear charge to an effective nuclear charge.
