out - and the water level in the bucket would drop.
             However, if you were to begin pouring water into the bucket at the same rate that it was leaking out, the water level in the bucket would stay the same because the rate at which the water is entering the bucket is equal to the rate at which it is leaking out. This is an example of dynamic equilibrium, and it applies to nearly everything that happens in the natural world.
             Diffusion occurs when a system is not at equilibrium. As an example, suppose you drop one drop of ink into a glass of water. At first, all of the ink molecules are in a small space and they are moving around in a random way. They move in straight lines and change direction only when they collide with each other or the surrounding water molecules. Some of the ink molecules near the edge of the drop move away from the center of the drop. As a matter of fact, most of the molecules move away from the center of the drop.
             Most of the molecules continue to move away from the original center of the drop. They move in all different directions, and some may even move back toward the center. Still, more are moving away from the drop than toward it until they find the wall of the glass. Then they start moving back toward the center again. More and more molecules bounce off of the glass until they start moving toward the center, then they pass the center and move toward the other side. Eventually the number of molecules moving away from the center equals the number moving toward the center, and equilibrium is established. At this point the molecules are evenly spread throughout the water, and diffusion stops. Have the molecules stopped moving? Is this a static or dynamic equilibrium?
             Several factors affect how fast a molecule will diffuse. The first of these is the kinetic energy of the molecule, which is most frequently measured as the temperature of the system. Molecules in a system at a higher temperature will have ...