- Pour 1-2 inches of oil into the jar.
- Pour a half-inch of water into the jar; it will sink below the oil.
- Add 2 drops of food coloring, and mix the food coloring gently into the water.
- Break an antacid tablet into quarters and drop one or two pieces into the jar. Watch the colorful, fizzy bubbles rise to the surface!
- Allow the colored water to settle back to the bottom, and drop in more antacid to start up your lava lamp again.
The Science Behind Lava Lamps
- Why do the oil and water separate instead of mixing?
The water is more dense than the oil. Liquids are made up of little particles called molecules. In the water, the molecules are packed closer together than in the oil, so the water sinks below the oil in the jar.
- Why does the antacid tablet make the lava lamp start bubbling?
When you add the tablet to the water, a chemical reaction happens. Mixing those two substances creates a gas — carbon dioxide — which is all of the little bubbles that you see. These bubbles are less dense than both of the liquids, so they carry the colored water to the top of the oil where they pop and the water sinks back to the bottom.
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