Pairs work together to determine whether unknown solutions are either acids or bases by using a red cabbage indicator solution. After determining the general pH of the unknown solution, classmates blow into the same indicator after resting and exercising, then observe any change in the color of the indicator. The teacher leads the class in a discussion on bioremediation to conclude the exercise.

Concepts

cells, acids and bases, acids, bases, cellular respiration, carbon dioxide, technology resources

Show More Show Less

Instructional Ideas

• Prior to this activity, present a lesson on pH, acids, and bases
• To avoid making this a standalone activity, use the lesson Cellular Respiration and Bioremediation mentioned in the prerequisite knowledge section
• Use the four solutions that were in the first part as a gauge for the amount of change of pH due to respiration

Classroom Considerations

• The red cabbage indicator solution should be prepared the day before it is needed
• Though working with household type-solutions, participants should wear eye protection during the activity

Pros

• The activity provides clear directions on what to do in order to complete the activity
• The post-activity assessment creates a connection to the activity and bioremediation

Cons

• The worksheet requests a histogram, but what is needed is a bar graph, not a histogram
• The activity does not make a strong connection between the first part of the activity and the second part

Common Core

6.SP.B.4 6.SP.B.5.a