[Hunble]

Modified:

Experiment #2

Begin the experiment “Acid Rain on the Reef” by discussing acid rain. Then explain to the students that chalk contains limestone just like the coral reefs. Explain to the students that this experiment will show how acid rain can harm the reef.

Explain that each group will be given two pieces of chalk, which will represent the coral reef, and two cups of saltwater.

The students will place a piece of chalk in each cup. Using a marker, students will write “acid” on one of the cups.

With the cup labled as "acid", the student will exhale into the cup and infuse it with Carbon dioxide from the student's breath.

Students will store cups overnight. Students will predict what will happen to the chalk in each cup.

[cogitator]

Here's a better experiment. Get a bottle/flask that you can fill with seawater and which you can seal. Fill it about 2/3 full of seawater. Accurately measure the pH. Then drop a chunk of dry ice into the flask. Wait a day and measure the pH again.