Carbon Dioxide and Ocean Acidification

Chris Lewis, City College of San Francisc
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Demonstrates the affect of increased dissolved carbon dioxide on water pH using a cheap, non-toxic acid/base indicator. Students bubble breath through a straw into red cabbage juice and note the color change.



Introductory oceanography or physical science course

Skills and concepts that students must have mastered

Basic understanding of pH and acid/base indicators. Basic understanding of the respiration reaction.

How the activity is situated in the course

Stand alone demonstration in lecture or lab.


Content/concepts goals for this activity

Solubility of carbon dioxide and its influence on water pH.

Higher order thinking skills goals for this activity

Formulation of a hypothesis and collecting and synthesizing observations.

Other skills goals for this activity

Working in groups.

Description and Teaching Materials

See attached supporting materials.
Carbon Dioxide and Ocean Acidification (Acrobat (PDF) 57kB Jun20 13)

Teaching Notes and Tips

See attached.


Observation of group results.

References and Resources

Included in activity sheet.