Search for Science Fair Projects

1000 Science Fair Projects with Complete Instructions

General Chemistry Science Fair Project

Magical Color-Changing Lava Lamp

Magical Color-Changing Lava Lamp | Science Fair Projects | STEM Projects
Prepare to be amazed by this incredible lava lamp experiment that uses red cabbage juice to reveal the hidden world of pH. See colors transform right before your eyes as you learn about acids, bases, and the science of color-changing reactions.


The hypothesis is that by combining red cabbage juice with Alka-Seltzer tablets, the color of the mixture will change due to the carbon dioxide generated.

Method & Materials

You will make red cabbage juice and mix it with baking soda. Then, you'll pour it into a glass filled with oil, add an Alka-Seltzer tablet, and watch as bubbles and colorful droplets dance around the glass.
You will need red cabbage, canola oil, baking soda, Alka-Seltzer tablets, a tall glass, and a way to extract cabbage juice (such as a blender or boiling method).


When the Alka-Seltzer tablet reacts with water, it releases carbon dioxide gas, which is acidic. The acidic carbon dioxide causes the cabbage juice to change color and the mixture to bubble. The colorful droplets rise through the oil because of their lower density and then sink back down when the carbon dioxide escapes at the top of the oil. It's fascinating to see the color of the cabbage juice change as it becomes more acidic due to the generated carbon dioxide.

Why do this project?

This science project is fascinating because it combines chemistry and visual effects. It allows you to explore the concept of pH indicators and how substances change color in response to changes in acidity or alkalinity. The lava lamp effect adds an extra element of excitement to the experiment.

Also Consider

Instead of using red cabbage juice, try using other pH indicators like red wine or blueberry juice to see if they produce different color changes. Add glitter to the mixture before adding the Alka-Seltzer tablet to create a sparkling lava lamp effect.

Full project details

You can find additional information and details for this science fair project here. Have fun exploring!
Share this Science Project:

Related Science Fair Project Ideas

Salinity and Temperature: A Science Project
Learn how temperature and salinity interact by testing the salinity of water in three jars at different temperatures!
Glowing in the Dark
Have you ever wondered how to make glow-in-the-dark stickers glow longer?
Exploring Salt Crystals
Let's explore how salt crystals form and how adding different ingredients can affect the size of the crystals!
Share this Science Project: