This resource provides a physical reaction. Hydrous and anhydrous calcium chloride react with water to produce physical exothermic and endothermic reactions.

[Free Registration/Login may be required to access all resource tools.] In this lesson, students study the difference between reactions that absorb versus release heat as well as how to measure this change in energy.

Description of the factors influencing gas solubility. This site also provides other chemistry related questions. Topics include dissolving solids into liquids, concentration, and stoichiometry.

In this experiment, three reactions are performed in a sealed Ziploc bag so that they can be observed. Students identify whether physical or chemical change has taken place.

[Free Registration/Login may be required to access all resource tools.] Describes the law of conservation of energy and how energy is conserved in chemical reactions.

[Free Registration/Login may be required to access all resource tools.] Covers the law of conservation of energy and how energy is conserved in chemical reactions.

Explanation of Noble gases and of how atoms attempt to fill their outermost valence shells for stability.

This site from Siegen University contains brief information and a step-by-step photo display of burning magnesium. The information is very short but the pictures are definately worth checking out.

Here's a full and understandable discussion of Reaction Rates and Equilibrium.

[Free Registration/Login may be required to access all resource tools.] Definition of activation energy and why all chemical reactions require it.

[Free Registration/Login may be required to access all resource tools.] Explains chemical property and chemical reaction.

[Free Registration/Login may be required to access all resource tools.] Provides an introduction to chemical reactions.

Find out what entropy and enthalpy have to do with a spontaneous chemical reaction. [3:44]

A simple lab activity that allows good data collection on heat of solution.