This experiment is designed to use common household products to demonstrate the function and importance of surfactant. You will be using milk and food coloring for this assignment. Think of the milk as the water and food coloring as the gas in the respiratory system. Refer to lecture and lab information and click here to read more information concerning the importance of surfactant so that you can relate it to the concepts of this lab experiment.
Part 1: Surface Tension
Surfactants lower the surface tension of water. To better understand this concept, you will complete the following activity to demonstrate and observe surface tension before you experiment with the effects of surfactant. All you will need for this activity is a penny, water, and an eyedropper or pipette.
Wash and rinse a penny in tap water, and then dry it completely with a paper towel.
Place the penny on a flat surface.
Use the eyedropper or pipette to drop individual drops of water onto the surface of the penny.
Count and record the number of drops of water that will fit on the surface of the penny before the water runs off. You will need to report this number in your lab report.
Sample Solution