Chapter 8: Electronic Structure and Periodic

Properties

Orbital Energies For Single Electron Systems

Penetration and Shielding

Orbital Energies

Electron Configurations

The Aufbau process (building up):Electrons will always populate the lowest energy

state available.

We will use several “rules”, plus our knowledge of electron orbitals to identify the electronic configuration of any atom

The Pauli exclusion principleNo two electrons can have all four quantum numbers alike.

Hund’s rulePopulate all degenerate orbitals (orbitals of the same energy) with a single electron before putting a second electron in any orbital. There are several exceptions to this rule.

Electron Configurations

Orbital Filling

Because of electron shielding, orbital energies are usually ordered as shown above

The Electronic Configuration of Carbon

The Electronic Configuration of N – Ne

Filling the d Orbitals

Classifying the Elements

When the elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically.

Alkali Metals

Alkaline Earths

Transition Metals

Halogens

Noble Gases

Lanthanides and Actinides

Main Group

Main Group

Electron Configurations and the Periodic Table

The Sizes of Atoms and Ions

Radii of Cations

Radii of Anions

Atomic and Ionic Radii

Electron Affinity

Periodic Properties of the Elements

Trends in Physical Properties

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Trends in Physical Properties