In this Activity, students build models of polarized water molecules using K’nex toy components and adhesive Velcro. Students investigate hydrogen bonding by shaking the models in various ways. They observe the resulting interactions and relate their observations to physical states of water and the difference between strong bonds and weak attractions.
In this Activity, students first prepare a gel using the superabsorbent polymer sodium polyacrylate (found in certain diapers) and water. The gel is split into piles and samples of different compounds are sprinkled on the piles. Students determine that ionic compounds break down the gel, while covalent compounds have no effect on the gel.
In this Activity, students use their deductive reasoning skills as they identify formulas of unknown elements and compounds modeled by paperclips. Each color of paperclip represents a different element, with linkages between different paperclips in appropriate ratios representing 20 unknowns.