Yummy! S’mores are on the way! Did you ever toast marshmallows over a campfire? The sweet treats singe on the outside and melt on the inside. Both the fire and the toasted marshmallows are evidence of chemical changes. In the process of burning, the wood changes to ashes and gases, and the outside of the marshmallow turns brown and crispy. Neither the wood nor the marshmallows can change back to their original form. That’s because burning is a chemical change and chemical changes are often impossible to undo. In this unit, you’ll learn about many types of chemical changes, including how they occur and why you can’t live without them.
This unit explains chemical bonding and how compounds form. It describes different types of bonds and how they affect the properties of substances. The unit also introduces chemical reactions and describes several different types of reactions. It takes a closer look at the chemistry of carbon and the chemistry of solutions. Nuclear chemistry is presented as well, including types of nuclear reactions.