The basics of chemical reactions were covered in the first chemistry book, including how to write and balance chemical equations that represent those reactions. There is also a quick review of chemical reactions in Chapter 1 of this book. We’re going to delve a bit deeper into certain kinds of reactions—ones that occur often enough that it’s useful for them to have their own special categories. As you go through this chapter, try to avoid seeing these separate categories as conceptually different from other reactions. The same basic principles govern all chemical reactions, regardless of the category. This free selection includes the Table of Contents, Safety Note, a How to Get Special Materials section, and the Index.