Science Project: Lava Lamp

Ever wonder how a lava lamp works? All that light and slow motion liquid is so mesmerizing you may think it’s magic, but really, it’s science. And when you understand the science behind it it’s easy to make your own lava lamp!

Groovy Lava Lamp!
Courtesy of howstuffworks.com

You Can Make Your Lava Lamp in Any Container
Courtesy of greatfamilyadventures.com

Homemade Lava Lamp in a 2 Liter Bottle
Courtesy of lanevids.com

Materials:

• Clear bottle or jar (a liter soda bottle works well)
• Food coloring
• Water
• Vegetable oil
• Glitter
• 1 Alka-Seltzer tablet
• Flashlight

Procedure:

1. Fill the jar ¾ of the way with oil. 
2. Fill the rest of the jar with water.
3. Add food coloring until you have your desired color.
4. Add a sprinkle of glitter.
5. Shine the flashlight so that it lights up the liquid in the jar. For extra effect, turn the surrounding lights off.
6. Cut the Alka-Seltzer tablet into 8 parts and drop one by one into the jar.
7. Watch as the color blobs climb up the jar and fall back down again, just like a lava lamp!

You must have noticed that when the oil and water were added to the jar they didn’t want to mix. That is because oil is less dense than water and so it rises to the top of a oil and water mixture. So here we have these layers of oil and water and then we drop a chunk of Alka-Seltzer tablet into the mixture. What happens?

Alka-Seltzer reacts with water to release Carbon Dioxide (CO₂) gas, which is less dense than both oil and water. So up and up it goes through both layers of water and oil and when it reaches the surface the bubble pops and the bead of colored water falls back down. Groovy!

Though a store bought lava lamp works by heating up wax in and oil solution, this homemade Lave Lamp makes a great science project or a even just a fun experiment to do with friends.

Have Your Say

Why do you think the lava lamp is named after lava? Share your thoughts in the comment’s section below!