Does Vegetable oil have a lower or higher density then water?
Vegitble oil is less dense than water so it will sit on the top of the water. Most lava lamps are made with a special type of silicone oil which is more dense that water when it’s at room temperature and sinks, but when warmed by the light, it expands enough to become less dense than water so it floats. Once it gets to the top it cools enough to become denser than water and sinks again. Thus, the continuous movement of the ectoplasm-like globules is explained.
