Magic Milk video…milk, food coloring, and dish soap…why does it react?”
At the start of the experiment, you have a pan of milk, mostly water, and the drops of food coloring (also in water solvent). The colors sort of “bead up”, mixing very slowly, because of surface tension between the milk (also containing milk fat, milk sugar, etc). When you put the soap into the center, it quickly spreads out toward the edges, because it is a “surfactant”, an agent that greatly reduces surface tension. When the advancing surfactant wave hits the colors, the surface tension relaxes and the drops of color can mix MUCH faster. The other thing that is happening is that the rapid mixing, caused by the introduction of surfactant into the system, causes turbulence that moves throughout the pan, causing the swirling patterns. There is a lot of randomness here, and that is why. I think it would be fun to see if changing the milk from “whole” milk to Skim milk would cause differences in what you see. This is because the fat content might change the relative hydrophobic/hydrophili
