Anyone can stack blocks, boxes, or books, but only those with a steady hand and a little understanding of chemistry can stack liquids. What if you could stack seven different liquids in seven different layers? Think of it as a science burrito while learning about density.

Let us know how you stack up with this Science Saturday project.

Our Lava Lamps are an example of density and heat with a waxy mesmerizing motion.

How Things Work explains the lava lamp.

In the lava lamp you have two liquids which are very close in density.

Oil and water are insoluble in one another (that’s where the expression “oil and water don’t mix” comes from), but oil and water have very different densities (a volume of water weighs a lot more than the same volume of oil). They won’t work, so you search to find two liquids that are very close in density and are insoluble.

Now you apply heat to the bottom of the mixture. In a liquid motion lamp, the heat usually comes from a light bulb. The heavier liquid absorbs the heat, and as it heats up, it expands. As it expands it becomes less dense. Because the liquids have very similar densities, the formerly heavier liquid is suddenly lighter than the other liquid, so it rises. As it rises, it cools, making it denser and therefore heavier, so it sinks.

This all happens in slow motion because heat absorption and dissipation are fairly slow processes, and the density changes we are discussing here are very slight.

While you’re in your laboratory, you can concoct these edible googley eyed monsters.