LESSON 7: Milk Rainbow

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92LESSON 1:Goofy Putty92LESSON 1:Goofy PuttyYou Be The Chemist Activity Guides |page 92You Be The Chemist Activity Guides |page 92You Be The Chemist Activity Guides |page 92You Be The Chemist Activity Guide |page 92LESSON 7: milk RainbowESTIMATED TIMESetup:5 minutes|Procedure:5 10 minutes DESCRIPTIONCreate swirls of color in milk and explore a propertyof liquids known as surface tension. OBJECTIVEThis LESSON will demonstrate the property of surfacetension and the effect that soap, a surfactant, has on thesurface tension of milk . Students will apply soap tomilk with food coloring on the surface to visualize theeffect of soap on the surface tension of milk . Thelesson can be extended to discuss a type of mixturescalled emulsions. CONTENT TOPICSScientific inquiry; states of matter; properties ofmatter; attractive forces (surface tension); mixtures MATERIALSoWhole milk oWaterproof plate or shallow bowl oFood coloring oLiquid dish soap oCotton swabsAlways remember to use the appropriate safetyequipment when conducting your to the Safe ty Firstsection in the Res o

Milk is a natural emulsion of fats (oils) and proteins spread throughout water. Raw milk will eventually separate, with the fat rising to the top. However, store-bought milk generally looks homogeneous. The reason is that most store-bought milk goes through a process called homogenization that breaks down the fat particles so the

  Milk, Raw milk