Color Changing Milk
by Sheri Christiansen
Students in Mrs. Christiansen’s 5th
grade science class are learning about the scientific method.
They are practicing forming questions, hypotheses, and
conclusions. Students are following the steps of the
scientific method when conducting science experiments.
Last week, students did an experiment to see what would happen if
they put Dawn dish soap on a cotton swab and placed it in a plate
of whole milk with four colors of food coloring.
Here’s how it works.The fats and proteins
in the milk are sensitive, and when soap is added, the weak
chemical bonds that hold the proteins in solutions are altered.
The molecules of protein and fat bend, roll, twist, and
contort in all directions. The food coloring molecules are
bumped and shoved everywhere making the invisible easy to observe.
Also, since milk is mostly water, it has surface tension.
Soap wrecks the surface tension by breaking the bonds between
water molecules and allows the colors to go crazy in the milk.
Many “Oooohs” and “Aaaahhhs” were heard from all over the
room during this colorful display.
