Invite students to think about common items they encounter everyday.
Offer the example of air. It's often something we think of as a simple singular thing. Ask students to turn and talk about what they think air really is.
Entertain various thoughts and then present the slide of air with the atomic model.
Second, show the "key" that displays the various atoms and their associated colors (the colors arbitrary, of course!) and have the students offer a new statement as to what air actually is.
About 78% nitrogen gas (N2) and 21%
oxygen gas (O2), with smaller amounts of other gases including water vapor, carbon dioxide, and argon. (Carbon dioxide and argon are not show in this model.)
Note: Student access to the "element key" may helpful during the next part of this activity.