Magic Milk Experiment
The Magic Milk Experiment is a fun way to learn about molecules by turning milk into an explosion of colors using simple household ingredients.
Difficulty Level: Kindergarten & up
Supply List:
shallow dish or bowl
Milk (whole or 2%, you need the fat!)
Dish soap
Q-Tips
Food coloring, the more colors the better!
Instructions
Pour enough milk to cover the bottom of the dish or bowl.
Add a few drops of food coloring in various places in the milk. Make sure to use 3-4 drops of each color to see the full effect.
Put some dish soap into a separate bowl, and allow your student to dip their Q-Tip in and cover the cotton.
Dip the Q-Tip into the milk and watch the colors explode! The best explosions happen when dipping into the food coloring.
Repeat
How does the magic work?
The key to turning your milk into magic is soap! Soap molecules consist of a hydrophilic (“water-loving”) end and a hydrophobic (“water-fearing”) end. Water molecules are polar molecules that can dissolve other polar molecules. Fat (and oil) molecules are nonpolar molecules, so they cannot dissolve in water. Because milk is a mixture of water, fat, vitamins, and minerals, the soap helps to break up the nonpolar fat molecules, and connect the milk’s fat & water.
As the soap molecules connect to the fat molecules, the food coloring molecules get pushed around, resulting in the color explosion! If the explosion slows and stops, add more soap to see if there are any fat molecules that haven’t attached yet. If so, the color explosion will begin again.
Older students Up-Challenge
If you have older students also participating, one way to up-challenge this activity is by having the student experiment using different types of milk. Remember, the more fat molecules, the better. So consider what could happen if you use skim milk, oat milk, evaporated milk, or even sweetened condensed milk!
