TOPS #12 Solutions

28 Task Card Activities



This unit begins with corn starch. Mixed cold, it forms a coarse suspension that clears by filtering or settling. When boiled it forms both a cloudy colloidal suspension and clear true solution. Concepts and vocabulary learned here are then applied to a series of tasks that clean muddy water. Alum coagulates the clay, chlorination bleaches all traces of food coloring, but only distillation makes it pure. Students then use rock salt, baking soda, Epsom salt and copper sulfate to study about crystals, concentration and saturation, plus variables that influence rates of dissolving and limits of solubility.