x
Breaking News
More () »

Columbia's Leading Local News: Weather, Traffic, Sports and more | Columbia, South Carolina | WLTX.com

Learn about density with this DIY lava lamp experiment

Help your student learn more about chemistry using supplies you likely already have at home.

COLUMBIA, S.C. — With students headed back to school, whether in person or online, it is important to keep learning hands on a fun. This experiment is all about density and you will get to create a DIY lava lamp in the process.

What you will need:

  • Vegetable oil
  • Water
  • Food coloring
  • Alka Seltzer tablets
  • Clear glass or container

Start by filling your container about three quarters full of oil.

Then, fill the rest of the container up with water and a few drops of food coloring. You could even add some glitter to the mixture as an added sparkle to the lava lamp.

The first thing to notice is that the water sinks to the bottom, while the oil stays on top. This is because water is more dense than oil.

Density equals mass divided by volume. So the heavier an object is, and the more compact it is, the more dense it will be.

Water molecules are also polar, meanwhile oil is a non-polar substance, which is why the two do not mix.

To create the lava lamp, all you need to do is break up the Alka-Seltzer tablets and drop them in the container.

The tablets will sink to the bottom and react with the water to create carbon dioxide bubbles. Water droplets will stick to these bubbles, and the combination becomes less dense than oil. This causes the water to rise to the top so the gas can escape.

Credit: WLTX

Once the gas escapes into the air, the water returns to its original density and sinks back down.

To keep the lava lamp going, just add more tablets to the container.

RELATED: The science behind why hurricanes spin

RELATED: Easy at home science experiments!