Activity Overview
Make a colorful milk mixture as you explore the concept of surface tension in this Magic Milk Experiment. The liquid soap breaks the surface tension and the milk molecules move apart. The molecules of the milk pull each other together, which stretched the surface of the milk into an invisible skin. Adding the liquid soap weakens the surface tension and makes the molecules move around. This makes the food coloring mix together and swirl around the plate of milk "magically".
Materials Needed
- Plate
- milk
- Food Coloring
- Dish Soap
- Cotton swab
How to Do It
- Pour some milk onto the plate.
- Add some drops of food coloring to the milk, using a few different colors if you can. We used gel food coloring but note that liquid food coloring works best.
- Dip your cotton swab into the dish soap and then dip the saturated swab into spots around the plate of milk.
- The colors will start to swirl around magically.
- Play around with adding the soap by redipping the swab into the soap and the milk.