F.9 – Temperature Dependence of Water – Density Ball
This apparatus is used to show the change in the density of water with change of temperature. Here an 8 cm diameter metal sphere has its weight adjusted to float in water at 15°C but it will sink when the temperature of the water is raised about 30°C.
A beaker is half-filled with cold tap water. Immerse the ball and it will float almost entirely submerged. Place the beaker on a tripod over a burner. As the water’s temperature rises, the ball will slowly sink.