Three simple ingredients unite to make a lava lamp style display in a glass jar!

Professor Figgy's Science Class from Sweet Paul on Vimeo.

Science behind the project: Carbon dioxide bubbles form due to a chemical reaction that takes place in water between the acid (citric acid) and the base (sodium bicarbonate—baking soda) that are both in Alka-Seltzer. The gas bubbles draw the colored water up through the oil layer to the top of the container. Once the bubbles are released, the colored water (which is more dense than and doesn’t mix with the oil) sinks back down to the bottom of the container.

You will need:

clear container of choice (recycled bottle or jar)

light-colored vegetable oil


liquid food coloring

Alka-Seltzer tablets

  1. Fill container about 1⁄4 to 1⁄3 full with water and add food coloring to achieve desired color.
  2. Carefully pour vegetable oil into container, creating a layer on top of the water. Fill to about 2 inches below container opening.
  3. Drop Alka-Seltzer tablets into container. They will sink directly through the oil layer and begin bubbling in the water layer, drawing the colored water up through the oil like a lava lamp!


Photography by Susanna Blavarg

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