Investigating Convection

Aim: To investigate the rate of convection in water at different temperatures.

Observations Table

Water temperature	Time for dye to complete one full circuit (s)	Description of convection current
Cold
Hot

Analysis

In which beaker did the convection current move faster?

Explain why hot water convects faster than cold water in terms of molecular kinetic energy.

The Bunsen heats the water near the base. This water expands, becomes less dense and rises, carrying the dissolved crystal upward. Cooler, denser water falls to replace it, creating a convection current. The purple dye makes this current visible. In hotter water, molecules have more kinetic energy and move faster, so the current circulates more quickly.