This model simulates the state changes of water. By heating up and cooling down the water molecules in the model, you add to and remove the kinetic energy from the molecules. Due to the intermolecular forces, these water molecules will then take more or less space. When they are cooled down enough, these molecules will form a crystallized structure, i.e., ice. This model can be used to explore the states of water, the relationships between molecules’ kinetic energy and space they may take, and the unusual space changes in water when it freezes.