In this interactive object, learners calculate the amount of heat evolved or absorbed in chemical reactions. Four practice problems are provided.

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 interactive object, the learner practices identifying charges on ions.

In this well-illustrated activity, learners examine the three types of intermolecular forces: dipole-dipole forces, London or Van der Waals forces, and the hydrogen bond. Two interactive questions are included.

In this interactive object, the learner examines the basic terms used in division. A quiz completes the activity.

Learners use basic math skills in a workplace situation.

In this interactive object, students view an animated depiction of Class 1 levers. A matching quiz completes the activity.

Students read an explanation of the values used for arterial blood gas analysis.

Students read about how acid/base balance affects a person's health. This activity includes animation.

Enzymes

Spelling

Order basic phrases

Basic Economics