Science Experiments with Alka Seltzer for Kids

by Jennifer Mullett

Create a variety of experiments using Alka Seltzer tablets for kids. Whether you choose to make a rocket, a lava lamp, a grenade or watch for chemical reactions, Alka Seltzer tablets provide many options for science experiments. Be sure to wear goggles and supervise each of the experiments with safety in mind. Experiments can be done in a classroom setting, at home and even at a birthday party.

Lava Lamp

Use a clear plastic bottle, fill it three-quarters of the way with generic cooking oil. Fill it the rest of the way with water. Add several drops of food coloring until the water is saturated with color. Break the Alka Seltzer tablets into several pieces. Add one piece at a time to watch the fizzing and bubbling. When you finish adding the tablets, put the cap on the bottle and tip it upside down. The water and oil remain separate to create the lava lamp effect.


Using an empty film container, fizzy water and Alka Seltzer tablets, create a film canister rocket. Start out slowly to get a feel for the experiment. Wear goggles for the duration of the experiment. Fill the canister with soda water, shake it and wait for the cap to pop off. Different combinations of water and shaking will yield different results. Next, add plain water and pieces of Alka Seltzer tablets and wait for the cap to pop off. Results will vary; keep a record of what works and try to beat the record.

Chemical Reactions

Add several torn pieces of red cabbage leaves to a large seal-able plastic bag. Pour in one cup of warm water and agitate it until the water turns blue. Add a quarter of the mixture to two different clear plastic cups. Experiment with changing the color of the water. Add one tablet of Alka Seltzer to a third cup with plain water in it. Once dissolved, add drops of this water to one of the blue water cups. Compare the color of the two cups of blue water. Experiment further by adding drops of lemon juice to the other blue cup water. Try to make the colors the same again.

Party Grenades

End your next birthday party with a grenade toss experiment. Alka Seltzer and vinegar will explode while confined in a plastic bottle when they collide with a hard surface such as cement. Make sure everyone wears goggles, and give each kid a bottle with white vinegar and food coloring. Find a safe area to launch the grenades -- an empty parking lot, driveway or basketball court -- add the Alka Seltzer tablets and place the cap on tight. Once the gases begin expanding, the bottle will expand slightly. Toss the grenades away from people and watch them explode.

About the Author

Jennifer Mullett started writing in 1998. She has published several short stories in Notebook Magazine, has ghostwritten news releases and articles for local companies and continues to write fiction. Mullett has a diploma in floral design from The Canadian Institute of Floral Design and a diploma in photographic studies from Lawrence College.

Photo Credits

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