Science Is Fun-Dancing Milk

Color, science "speremints", and messy play. These are three things that really trip Sam's trigger. This fun project is something I saw recently on a friend's Facebook page and just knew he would love to play with. We made a bubbly, wiggly, gyrating, dancing color wheel with a plate, milk, food coloring, dish soap, and a Q-tip. 

 

 

Pour enough milk onto a plate to cover the bottom. 

Drop food coloring onto the milk.  

Dip a cotton swab in dishwashing detergent liquid. 

Give your kiddo the coated swab so he/she can place it in the milk at the center of the plate. 

 Don't stir the milk; it isn't necessary. The colors will swirl on their own as soon as the detergent contacts the liquid.

Sam could only be so still with the soap and the cotton swab. The initial reaction of the food coloring in the milk was to make a fantastic star burst. Once he saw that he wanted to swirl and twist the cotton swab in the colors. Ok, that's not exactly following the directions but he was having a blast  oooo-ing, ahhh-ing, and generally loving the experience so whatever. It was his experience to enjoy.

 



 

Here he is going back for more soap. I do wish I'd waited until the milk was room temperature as that evidently works better in this experiment but as soon as Sam saw me setting up the supplies, he pulled up a chair and got excited. That's really the point of cool, fun projects like this anyway isn't it? To get kids excited about science in a hands-on way.

 

Mission accomplished once again!

 

We attempted to get video of the color changing magic but they just didn't turn out to be of very good quality so I found links to much better videos HERE and HERE.

 

If your kiddo is old enough to want to know, and be able to understand, how it works, here you go. Thank you Steve Spangler Science for the following explanation.

 

Milk is mostly water but also contains vitamins, minerals, proteins, and tiny droplets of fat suspended in solution. Fats and proteins are sensitive to changes in the surrounding solution (the milk).

The secret of the bursting colors is the chemistry of that tiny drop of soap. Dish soap, because of its bipolar characteristics (nonpolar on one end and polar on the other), weakens the chemical bonds that hold the proteins and fats in solution. The soap's polar, or hydrophilic (water-loving), end dissolves in water, and its hydrophobic (water-fearing) end attaches to a fat globule in the milk. 

The molecules of fat bend, roll, twist, and contort in all directions as the soap molecules race around to join up with the fat molecules. During all of this fat molecule gymnastics, the food coloring molecules are bumped and shoved everywhere, providing an easy way to observe all the invisible activity. As the soap becomes evenly mixed with the milk, the action slows down and eventually stops. 

Try adding another drop of soap to see if there's any more movement. If so, you discovered there are still more fat molecules that haven't found a partner at the big color dance. Add another drop of soap to start the process again.