Super Fun Science

Today we bring you an interesting and easy experiment you can do at home. By doing this simple procedure you will experience examples of water tension, suspending solids in a liquid solutions and also learn a bit about pigments.

Here it is!

Color Changing Milk.

Background:
Milk is a liquid made up water, vitamins, minerals, proteins, and droplets of suspended fat. Fats and proteins are sensitive to changes in the surrounding solution (in this case, the milk).

Like all substances, protein molecules are attached to each other by weak chemical bonds. With the addition of soap, these bonds begin to break down.

Soap forms micelles which attract the fat molecules inside it. These form fat globules as the fat separates from the milk solution. Water and minerals are left in the solution and the color is the result of the food color added. Milk is mostly water, so the surface tension on the surface is weakened with addition of soap, making the milk more easily blend with the colors.

Problem:
To see the effect of the addition of soap and food colors to milk.

Materials:
Milk (whole or 2%);
Deep plate with molded edges
Food coloring (red, yellow, green, blue);
Dish-washing soap (Dawn brand works well);
Cotton swabs.

Procedure:
Pour milk into a deep plate with molded edges and allow it to settle.

Add food coloring to the milk near the center of the plate.

Touch the center of the milk with a cotton swab very gently.

Place a drop of liquid soap on the tip of the swab and dip it back again into the milk and hold it there for 10 to 15 seconds. Suddenly colors burst and the liquid looks like a riot of colors.

Conclusion Questions:
Try repeating the experiment using water in place of milk. Will you get the same eruption of color? Why or why not? What kind of milk produces the best swirling of color: skim, 1%, 2%, or whole milk?

August 15th, 2008 | Tags: Education, experiment, Homeschool, how-to, Milk, water tension | Category: Experiments | Subscribe to comments | Leave a comment | Trackback URL