Lemon Juice Rockets
Launch a capsule using gas pressure produced by water, lemon juice and baking soda.
What you need
- An empty, 16 ounce, plastic soda or water bottle
- A cork (capsule) that tightly fits the soda bottle. If you can't find a cork that fits, you might want to wrap it in tape.
- paper towels
- toilet paper
- lemon juice
- baking soda
- water
- other acids, like cola, or vinegar
- scissors
- funnel
- safety glasses
What to do
Step 1. Check with an adult before you begin.
Step 2. You will want to do this outside.
Step 3. First, tear the paper towels into strips and attach them to the cork with tape. This makes the cork look more like a rocket capsule.
Step 4. Then, cut a small square out of toilet paper, put about a teaspoon of baking soda in the middle of the square, and fold in the sides to make a little packet.
Step 5. Put the funnel into the opening of the bottle.
Step 6. Pour a half inch of lemon juice into the bottle, and then add water until it is a little less than half-way full.
Step 7. Put on your safety glasses. Drop the baking soda packet into the soda bottle, close the bottle with the cork, shake the bottle, and stand back for lift off.
What's Happening
Here's the reason the cork shoots up. As the water and lemon juice soak through the toilet paper, the baking soda reacts to produce carbon dioxide. Carbon dioxide is a gas. As more gas forms, pressure builds up inside the bottle and sends the cork flying.
This is a simple demonstration of Newton's Laws of Motion. The capsule lifts off because it is acted upon by an unbalanced force (First Law). This is the force produced when the capsule is blown out of the bottle by the carbon dioxide. The amount of force is directly proportional to the mass of water and gas expelled from the bottle and how fast it accelerates (Second Law).
Tips
Lemon Juice is an acid, and baking soda is a base. When they are mixed together they produce carbon dioxide. Try launching your rocket by mixing other acids with the baking soda. Make a prediction, and then test it out.