At this site from Purdue University, Electron Configurations, the Aufbau Principle, Degenerate Orbitals, and Hund's Rule are detailed. Includes learning exercises and answers.

In this module students explore how matter is classified, the history of atomic theory, subatomic particles, modern atomic theory, electron configuration, the periodic table and its trends, and spectroscopy.

Analyze the electron configuration of the of the first twelve elements on the Periodic Table.

A description of the arrangement of elements on The Periodic Table based on electron configuration.

This page provides a thorough and comprehensible discussion of the structure of the atom. Includes helpful diagrams and instructions for filling electron shells, reading the Periodic Table, and drawing Lewis Structures.

The Pauli Exclusion Principle shows how electrons fill atomic orbitals. Includes biographical information on Wolfgang Pauli.

Each electron has a set of quantum numbers that specify it's location, orbital, and energy in a unique manner.

This site from WebChem contains information on the subject of bonding with an emphasis on valence and core electrons.

This lesson focuses on the periodic table and the configurations. In the modern periodic table, elements are in order of atomic number in periods and groups. Electronic configurations model how electrons are arranged in atoms. A link to...

Acting as a subtopic of the General Chemistry Virtual Textbook's section on Atoms and the Periodic Table, this site discusses atomic electron configurations. Specifically, the Aufbau rules are discussed with information on energies of...

[Free Registration/Login may be required to access all resource tools.] Covers electron configurations of transition elements.

A description of quantum theory, the Bohr model of the atom, the quantum mechanical atom, the Scrodinger equation, and quantum numbers.

This interactive periodic table developed for Teachers' Domain provides detailed information about the chemical properties of elements and illustrates the electron configurations that determine those characteristics.

Site that discusses trends in ionization energy across and down the periodic table. Apparent contradictions are explained using electron configurations.

The number of protons in the atom of an element determines its place in the Periodic Table. The number of electrons in an atom is the same as the number of protons. These electrons are arranged in shells or 'energy levels' around the...

The Pauli Exclusion Principle requires that all electrons in an atom have unique energy levels.

An explanation of Hund's rule and how to apply it to quantum mechanics. A mathematical-based explanation.

An explanation of how photoelectron spectroscopy can be used to detect electron structures in atoms or molecules.

[Free Registration/Login may be required to access all resource tools.] Covers Group I elements, electron configuration, and reactivity.

An explanation of the Pauli Exclusion Principle in mathematical terms.

At this University of Texas site, atomic orbital occupancy, quantum numbers, the Aufbau Principle, and periodic trends are described in detail.

Explains what Bohr's model of the atom is, the characteristics of the ground and excited states of an atom, and the electron configuration for each in the example of Phosphorus.

View the approximate locations of electrons in valence shells 1s through 4f.

The periodic table was laid out using valences or the electrons in the outermost shell.