Description:

With this project, you can make your own (temporary) lava lamp with household materials! It's easy and safe, and it looks very cool.

Materials:

• Bottle/Jar
  

• Oil
  

• Food Coloring
  

• Water
  

• Alka Seltzer Tablets
  

• A Light
  

Instructions:

1. Fill your jar most of the way with oil

2. Fill the rest of the flask with water. The water will sink to the bottom under the oil.

3. Add a few drops of food coloring; your choice of color. The food coloring is water-based, so it will also sink and color the water that is now at the bottom of the flask.

4. Break an alka-seltzer tablet into a few small pieces, and drop them in the flask one at a time.

5. Watch your lava lamp erupt into activity! As the reaction slows down, simply add more alka-seltzer.

Explanation, Questions, and Review:

The reason why the oil and water don't mix is because the oil is nonpolar and the water is polar. The alka-seltzer reacts with the water to produce carbon dioxide gas bubbles. These stick to the water droplets. The water/gas combo is less dense than the oil, so they rise to the top of the flask. At the top, the gas bubbles pop and escape into the air, allowing the dense water to sink back to the bottom again.