SAT Subject Test Chemistry




Chemical Formulas

Chapter Summary

The following terms summarize all the concepts and ideas that were introduced in this chapter. You should be able to explain their meaning and how you would use them in chemistry. They appear in boldface type in this chapter to draw your attention to them. The boldface type also makes it easier for you to look them up if you need to. You could also use the search or “Google” action on your computer to get a quick and expanded explanation of these terms, laws, and formulas.

binary compound

net ionic equation



percentage composition

stock system

empirical formula

polyatomic ion

ternary compound

formula mass


true formula

molecular mass


Law of Definite Composition

Law of Multiple Proportions

Internet Resources

Online content that reinforces major concepts discussed in this chapter can be found at the following Internet addresses if they are still available. Some may have been changed or deleted.

Interactive Practice on Naming Ionic Compounds

This site offers an interactive practice on naming ionic compounds.

Chemical Formula Writing

This site offers an interactive quiz on writing chemical formulas.

Naming Chemical Compounds

This site offers a Shockwave Flash exercise on chemical nomenclature.

Balancing Chemical Reaction Equations

This site offers a tutorial on balancing simple reaction equations with helpful step-by-step hints.