Order early for pre-holiday delivery. Flinn will be closed December 24th, 2025,
through January 4th, 2026, reopening Monday, January 5th, 2026.
Orders received after 10:30 AM Central Time on Tuesday, December 23rd, 2025,
will ship after we return.
DC95023
Price: FREE
When molecules are the size of balls, phase changes such as melting and evaporation can be very “moving” events! A tubful of rubber balls is a perfect demonstration device for comparing the energy and motion of molecules in the solid, liquid, and gas phases. It’s time to put the “kinetic” back into the kinetic–molecular theory!