Final answer:
To show diffusion, place drops of blue food coloring in warm water in a fish tank and watch as the coloring spreads until the water becomes evenly colored. The rate of diffusion is higher at the beginning and slows as concentration levels out. The process reveals how molecules move from areas with many molecules to those with fewer, achieving equilibrium.
Step-by-step explanation:
To demonstrate diffusion in action using a fish tank full of warm water and blue food coloring, one would carefully add a few drops of the coloring to the water and observe. Over time, the blue coloring will begin to spread throughout the water, even without stirring. This spreading out of the blue food coloring molecules is known as diffusion, and it occurs because the molecules move from an area of higher concentration to one of lower concentration. Initially, the rate of diffusion is high since there is a significant difference in coloring concentration between the drop of food coloring and the surrounding water. As the color spreads, the rate decreases, because the concentration differences become smaller.
In a warm fish tank, the process may also involve convection rolls, where the warm water rises and cooler water descends, creating currents that can further spread the food coloring, demonstrating both diffusion and convection. However, even without these currents, diffusion alone would eventually result in the water becoming an even color all around, showcasing the natural tendency of molecules to move towards a state of equilibrium.