In this interactive and animated object, students distribute the valence electrons in simple covalent molecules with one central atom. Six rules are followed to show the bonding and nonbonding electrons in Lewis dot structures. The process is well illustrated with eight worked examples and two interactive practice problems.

In this animated activity, learners examine the terms "half-reaction," "oxidizing agent," and "reducing agent" and follow five interactive examples to balance equations for oxidation-reduction reactions. Three problems are provided as a self-check.

Learners examine the method for calculating the atomic weight of copper from the natural percent composition of each of its two isotopes.

Students read an introduction to the lab equipment used to contain and dispense chemicals. A quiz completes the activity.