The interaction of the detergent with the fat in milk results in a beautiful swirl of color that will likely impress students. Science as Inquiry Standards Abilities Necessary to Do Scientific Inquiry Students identify questions that can be answered by scientific investigations. After observing drops of food color in water, they are asked to think about what would happen if food color were dropped into a glass of milk. Students conduct an investigation, observing the swirling motion that results from putting food colors and dishwashing liquid into milk.
Students use evidence from their investigation to propose explanations.
Students explain how the amount of milk fat affects the mobility of the food color drops before and after liquid detergent is added. Students analyze alternative explanations for why the drops of food color did not spread out in the whole milk as they did in the water. Properties of Objects and Materials, Grades K-4 Objects have observable properties, including color and interaction with other objects. Properties and Changes of Properties in Matter, Grades 5-8 Substances have different characteristic properties. The types of substances included in a mixture play an important role in determining the properties of the final mixture.