CH110 Lecture Notes - Lecture 5: Pauli Exclusion Principle, Aufbau Principle, Electron Configuration
Document Summary
Uses [ ] symbol to represent a noble gas configuration. The [ ] symbol represents the core electron configuration only. The valance electron configuration is written as usual (valence electrons = electrons in the highest n shell) The periodic table is arranged in order of increasing electrons. The orbitals of the atoms are filled with these electrons. Each orbital has a maximum capacity of 2 electrons (pauli exclusion principle) The atoms in the periodic table are in their ground states (most stable) Conditions for electron arrangement in atomic ground states: each electron in the atom must occupy the most stable available orbital, no two electrons can have identical quantum numbers (pauli exclusion principle, orbital capacities: Each row is labelled with the highest principle quantum number. Each column (group) is labelled with its group number. The actinides and lanthanides (grey) do not have column numbers. Each element shows its least stable occupied orbitals.