You've noticed that that amount of carbon dioxide dissolved in soda seems to vary with changes in temperature. You know that you need oxygen to breathe. Fish and other critters that live in water also depend on oxygen. Many of you have suggested that fish breathe oxygen that is dissolved in the water. What evidence can you give to support this idea? Discuss this with your group.

Does the amount of oxygen dissolved in water affect the fish? What environmental conditions might affect the amount of oxygen dissolved in water in the ocean and in ponds and streams? What do you think would happen to fish if the amount of oxygen got too low?

Predict how the amount of oxygen dissolved in water might change with an increase in temperature of the water. Discuss this with your group. Be prepared to explain your reasons to the class.