The Sweeter Side of Density

The concept of density represents a treasure trove of demonstrations, experiments, and discrepant events. Shortly after learning about common units of measurement, students frequently learn about density as an intensive physical property. The combination of oil and water is a common demonstration that simultaneously demonstrates density and miscibility. Regardless of how they are combined, oil and water, being immiscible, separate into distinct layers with oil on top. This classroom activity is an example of miscible liquids, which can be carefully combined to make a layered heterogeneous solution. Students determine the density of different sugar solutions and then devise a method for layering them in a graduated cylinder. Dyeing the solutions with food coloring results in a rainbow-colored heterogeneous mixture.