Summary Identify, make and separate various heterogeneous mixtures. Science content Chemistry: Atoms, Molecules (3-7) Chemistry: Physical Changes, Solutions, Mixtures and Separating (2, 4, 5, 6) Activities in this lesson Mixtures: solutions, suspensions and colloids Separating a heterogeneous mixture Butter Oobleck Materials materials in the activities optional: transmission microscope, slides and coverslips, pipette to look closely at the particles in colloids Procedure Discover and define different kinds of heterogeneous mixtures (solutions, suspensions and colloids) with the Making Mixtures activity. Separate a heterogeneous mixture using different methods. Make colloids: butter is recommended as there are three colloids in its making (cream, whipped cream and butter). Alternatively, make oobleck or flubber, which are also colloids. Set up a transmission microscope for small student groups to visit. Make a slide of a milk drop (2% milk works fine). Under 100X power you can see the fat droplets, and at 400X power you can see that they are variously-sized. They are all small enough to stay in the milk, and not settle out as a separate layer. Hence they are a colloid. Make a slide of oobleck to see the cornstarch particles, with a different appearance from the milk. See attached files for summary of mixtures including colloids. Attached documents Mixtures summary.pdf Grades taught Gr 4 Gr 5 Gr 6 Gr 7
