Transcript Electron Configurations - Warren County Public Schools

Electron Configurations
Chapter 5
Aufbau Principle
 Aufbau Principle: Electrons occupy the
lowest energy orbital available
Aufbau Principle
Pauli Exclusion Principle
 Pauli Exclusion Principle: a maximum of
two electrons may occupy a single atomic
orbital, only if electrons have opposite
spins.
Hund’s Rule
 Hund’s Rule: single electrons with the
same spin must occupy each equal energy
orbital before additional electrons can fill
said orbitals.
Orbital Notation
 Box represents orbital.
 Each box is represented by its principle
quantum number and sublevel associated
with the orbital.
 Ex: C
Electron Configuration Notation
 Principle energy level, sublevel and
superscript representing number of e Ex: C
 C 1s22s22p2
Nobel Gas Notation
 Uses Nobel gases to abbreviate electron
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configuration notation.
Ex:
Na
Na 1s22s22p63s1
Can be abbreviated by using the previous noble
gas
Ne 1s22s22p6
Na [Ne] 3s1
Valence Electrons
 Valence Electrons: electrons in the
outermost orbitals
 Chemical properties
 Main-group elements periodic table
 Ex: C
Electron-dot Structure
 Consists of atomic symbol, surrounded by
dots representing the atom’s valence
electrons.
 Ex: C
Exceptions
 Tendency for half filled orbital.
 Cr, Mo, Cu, Ag, Au
 4s13d5, 5s14d5, 4s13d10, 5s14d10,
6s14f145d10