How does a Lava Lite work?
Like your oil and water, the “lava” in a Lava Lite doesn’t mix with the liquid that surrounds it. When it’s cool, the “lava” is a little bit denser than the liquid surrounding it. When the “lava” rests on the bottom of the Lava Lite, the light bulb in the lamp warms it up. As it warms up, the “lava” expands a little. When it expands, the “lava” stays the same weight but it takes up more space-so it’s less dense. When it’s warm enough, the “lava” is less dense than the surrounding liquid, and so it rises up to the top to float. At the top of the lamp, it cools down, becomes more dense, and sinks once again. This cycle repeats over and over as the “lava” warms up and rises, then cools down and sinks. Where did this experiment come from, anyway? Exploratorium Teacher-in-Residence Eric Muller created this activity while playing with his food in a Chinese restaurant.