Introduction: Psychedelic Milk
Now I know what you're thinking, and no, it's not that kind of milk. This psychedelic milk is a fun and simple science experiment that is easy to do and whose visual results may just be even more mesmerizing than a campfire.
(Although come to think of it, doing this experiment would probably pair well with that other psychedelic...)
The great thing about this fun bit of science, is that you probably already have everything you need to try it at home!
Let's get to making >>>
Step 1: Supplies
- whole milk
- liquid food coloring
- liquid dish soap
- powdered dishwasher soap
- small plates
- tiny rocks
How the Science Works
When you add soap to whole milk, the surface tension is broken causing an initial burst of movement, and then the soap molecules start bonding to the fats and proteins in the milk, causing even more movement. The food coloring we add to the milk doesn't play any role in the science of that 'liquid dance', but it does a great job of illustrating the movement.
You can keep adding soap to create more changes in the movement/color patterns until all the bonding has occurred. After the bonding is done, adding more soap will have no effect. It differs from try to try, but the bonding process takes anywhere from 3-5 minutes if your dish is approx. 4" in diameter.
I've attached a printable experiment note taking sheet that will allow you (or your kids) to keep track of what you've tried (different: dish diameter, soap application, amounts of color) and how awesome each one was (1-5 stars). Use colored pencils/markers to indicate where you tried putting drops of food coloring. (like pictured)
Why This Experiment is Awesome
1. Like snowflakes, each time you do this, you will get completely unique results.
2. It's a super low maintenance way to keep kids (and big kids) busy for hours.
3. It has the potential to get kids really excited about science = future doctors.
4. Because, science is rad. Simple as that.
Step 2: Milk It
Fill the bottom of a small dish/plate* with whole milk** until it's 1/4 to 1/3" deep.
*Try using different sizes of plates to see if having more milk/surface area produces different results.
**It's important to use whole milk because it's the fat in the milk that bonds with the soap, creating the movement. Using 2% or skim milk will produce less exciting results.
Step 3: Drop It
Add 1-2 drops of 3-4 different colors of food coloring in the center of your milk.
FOR MORE FUN: Try the experiment a few more times, putting the colors in different areas of the milk to see how that changes the coloring food dance party.
Step 4: Soap Application #1: Drop(s) of Liquid Dish Soap
Place your food coloring drops and add a drop or two of liquid dish soap to the center of the dish.
Watch the magic happen. I mean science.
Step 5: Soap Application #2: Liquid Dish Soap on a Q-Tip
Once again, add the food coloring in the center of the milk. Dip a q-tip in liquid dish washing soap and place it in the center of the milk. Hold it there for a few seconds.
If you'd like to add some swirly fun into the mix, twirl the q-tip slowly before taking it out of the milk.
Step 6: Soap Application #3: Sprinkled Dishwashing Powder
Repeat the color drops process and then scatter a pinch of powdered dish soap over the surface of the milk.
See how different the movement of the color is from the liquid drops.
Step 7: Soap Application #4: Tiny Rock Dipped in Liquid Dish Soap
Add the food coloring to the milk. Pick up a very tiny rock with a pair of tweezers, dip the rock in liquid dish washing soap and drop it into the center of the milk. It will sink and continue to release soap creating it's own style of color movement.
Yay, that's it! I hope you have fun trying this.
If you have any other suggestions of different ways to do this experiment, please leave a comment below.
Happy science making!