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Can objects move by themselves? Without a visible force being exerted on them? Here is a chance to find out using mothballs and other objects. What you will discover speaks to the power of chemical forces.

• A glass jar filled halfway with water
• A 1/4 cup of vinegar
• 2 tsp of baking soda
• A few mothballs

1. IMPORTANT: This mixture is not meant to be drunk. Mothballs can be toxic, so do not put them in your mouth! And, make sure to wash your hands after you handle mothballs.
2. Okay, so first, add the vinegar to the water, and add the baking soda. Stir gently.
3. Now, drop in a couple of mothballs. What happens?

Why It Works:

The surface of a mothball is not smooth-it has irregularities. Your mixture of vinegar and baking soda creates a chemical reaction, which results in carbon dioxide bubbles. When enough bubbles collect under the mothball, it raises the mothball to the surface. At the surface, the bubbles escape into the air outside of the water, and the mothball sinks again.

This experiment can be done with other light objects that have uneven surfaces, so try some out.