States of Matter- Potatoes and Hydrogen Peroxide- Free Lesson

You can show the three states of matter solid, liquid and gas by demonstrating a simple experiment using hydrogen peroxide and a potato.

The students will be able to explain the reaction that occurs when hydrogen peroxide comes in contact with a potato.  The students will be able to identify the three states of matter present in this experiment. 

1) Safety Glasses

2) Hydrogen Peroxide

3) Potatoes, whole and shredded

4) A Beaker, or another small glass container

1. Have students identify the two states of matter they have to conduct the experiment. The potato being the solid and the hydrogen peroxide as the liquid. Have students make predictions of what they think might happen when they add the hydrogen peroxide to the potato.

2. Have student place a small amount of shredded potatoes into the beaker, and add hydrogen peroxide to the beaker. Observe the reaction that takes place. Small bubbles will appear on the potato. Have students record their observations.

3. Explain to the students that catalase is an enzyme found in most living things. Catalase that is present in damaged cells reacts and breaks down hydrogen peroxide. It is the reason why when we drop hydrogen peroxide into a cut it also foams up.

4. The end reaction of the catalase of the potato breaking down the hydrogen peroxide forms oxygen bubbles which are the state of matter gas.

5. Have students predict what would happen if they drop a small amount of hydrogen peroxide onto a whole uncut potato. Have students record their observations. There is no reaction as the catalase in still present in cells that have not been broken.

Identify and review with students the three states of matter: solid, liquid, and gas.  Explain to students that they will be conducting an experiment where they will use a solid and a liquid to create a gas.  At this time you should go over the safety precautions of the hydrogen peroxide and the importance to keep safety glasses on.

Discuss with students the difference in these two experiments.  Have students describe the reaction between the potato and hydrogen peroxide using the three states of matter. Discuss the nutritious facts about potatoes.