Hooked on Science: Lava lamp

Create your own lava lamp with a few materials from the kitchen.

Materials

* Plastic bottle with cap

* Vegetable oil

* Water

* Food coloring

* Alka-Seltzer tablet

Instructions

STEP 1: Fill the plastic bottle three-quarters of the way full with vegetable oil.

STEP 2: Fill the plastic bottle the rest of the way with water.

STEP 3: Place several drops of food coloring into the plastic bottle.

STEP 4: Break the Alka-Seltzer tablet into two pieces.

STEP 5: Place each piece into the bottle.

Explanation

This experiment proves water and oil don't mix. The carbon dioxide gas created when you dropped the pieces of Alka-Seltzer tablets into the mixture causes the colored water blobs to push to the top through the oil.

Jason Lindsey is a science outreach educator with Hooked on Science. Check out his website www.hookedonscience.org for webcasts and experiments that might get you hooked on science. Send him your science questions at jlindseyhookedonscience.com. More science experiments can be found at www.semissourian.com.