Monster Eyes

Learn more

This spooky science trick is brought to you by "surface tension". Water molecules are tight-knit best friends that love to cling to one another, pulling tightly together at the surface to form a flexible, invisible "skin" called surface tension. When you drop food coloring onto water, or in this case glue, the lightweight dye floats gently on top of this stretched-out liquid shield. But the moment a drop of dish soap hits the surface, it acts like a molecular wrecking ball! Soap molecules have a hydrophilic (water-loving) head and a hydrophobic (water-repelling) tail, which rushes in to wedge itself between the water molecules, instantly shattering their strong bonds. As the surface tension collapses at the center, the remaining unbroken surface water snaps backward toward the edges of the bowl, dragging the food coloring along with it in a burst of swirling colors.