In this screencast, learners examine hearing and balance. Detailed drawings of the outer, middle, and inner ear structures are included.

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 object, students examine what happens when electrons share molecules.