Lava Lamp

Students create their own lava lamp using only oil, water, dark food coloring, and a fizzy vitamin-C tablet. They predict how the liquids will behave, imagine and draw their design, then build it layer by layer and test what happens with a half tablet versus a whole one. Along the way, they discover why oil and water don't mix and how carbon dioxide bubbles lift colored water to the top, a hands-on lesson in density and chemical reactions.