By: Doug De La Matter, Retired, Madawaska Valley D.H.S, Barry’s Bay, ON
Item #: AP6888
The “Bouncing Ball” Distillation Chemistry Demonstration Kit will help students visualize key concepts of the kinetic–molecular theory. A tub full of balls is used to compare energy and motion of molecules in various phases.
Phase changes, such as melting and evaporation, can be very “moving” events when molecules are the size of balls! A tub full of jumbo rubber balls is a perfect demonstration device for comparing the energy and motion of molecules in the solid, liquid and gas phases. What happens when the tub is shaken, gently at first, and then with more and more energy? Relate what happens to the balls to the changes that take place on a molecular level when a solid melts or a liquid evaporates. The “bouncing ball” demonstration will help students visualize key elements of the kinetic–molecular theory—how close together the molecules are in a solid, liquid and gas; their relative motion; and the attractive forces between them. Isn’t it time you made the kinetic–molecular theory truly kinetic?
Concepts: Kinetic–molecular theory, phase changes. Time Required: 20 minutes. Materials Provided: Clear plastic container with lid and 14 rubber balls, assorted colors.