In this interactive object, learners determine the limiting reagent and the excess reagent in chemical reactions. Learners test their knowledge by solving three problems.

Students read different definitions of "acids" and "bases." In an interactive exercise, they identify if a substance is an acid or a base.

In this colorful, interactive object, learners examine how materials on the nanoscale compare with those on the macroscale. The focus is on the difference between macroscale and nanoscale gold in both color and melting point.

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, learners examine the properties of the peptide bond and how the bond relates to the structure of hair.

In this animated lesson, learners read about the disulfide bond, the second strongest chemical bond in the hair. This bond can only be altered by chemicals.

In this animated object, learners examine how the heating or cooling steps in a manufacturing process work to control a chemical reaction.

Students read an explanation of chemical formulas in this animated activity. A quiz completes the object.

Learners read about lab equipment and basic safety measures. In a quiz, they view photos and determine if the lab technicians pictured are using safe practices.

A simple pairing game, through the correct combination of reactants and products, to complete the chemical reaction equation.

Changes in Matter

Use your knowledge of elements, mixtures, compounds, and chemical changes to beat the game!

Physical therapist practice areas