Summer is in full swing, but to stop summer slide, we still like to engage in learning activities. We love trying out new science projects in the summer, and they get bonus points if they are easy to set up! The magic milk science experiment is a classic experiment in chemical properties and chemical bonds. Using several kinds of milk, kids will learn all about how molecules bond together and will get to have fun seeing pretty colors form at the same time. Just make sure your kids don’t try to drink the milk after it’s been soaped, as they will NOT be happy with the taste.
MATERIALS NEEDED FOR THE MAGIC MILK EXPERIMENT:
You need just a few materials to make the magic milk science experiment work!
- Milk (whole, skim, and 2 percent)
- Liquid food coloring
- Glitter (we added it just for fun)
- Shallow container
- Toothpick or cotton swab (or you can do like we did and use the bottom of a cocktail umbrella)
First, fill three shallow containers will milk. Put whole milk in one, skim milk in another, and 2 percent in the third.
Drop a few drops of food coloring scattered across the surface of the milk. We used green, blue, and yellow because that felt like summer to us.
Dip your toothpick in dish soap.
Gently touch one of the drops of color on the milk.
Suddenly, all the colors will swirl and scatter.
Compare the different moving speeds with the various types of milk. In our experiment, the whole milk had the most dramatic “skating” effect. This is due to the higher fat content of whole milk, as explained below.
THE SCIENCE LESSON
Milk contains vitamins, proteins, minerals, and fats in addition to water. The fat and protein molecules are sensitive to changes in the environment. Soap is known as a non-polar molecule. When the soap is added to the milk, the soap molecules bond with the non-polar fat molecules. This causes the fat and soap to be carried quickly across the surface of the polar water molecules, creating the startling effect of fast-moving color. The more fat, the faster the colors will swirl.