How is the behavior of food coloring in the cool and heated water different? What caused the differences in their behavior?

Answer:

In the cool water, the food coloring stayed at the bottom of the container with very little movement. In the heated water, the food coloring rose to the top, spread to the sides, and then sank back down. This difference is caused by convection currents; the heat source makes the water at the bottom less dense, causing it to rise, while the cooler, denser water at the top sinks.