How is dynamic equilibrium established within a saturated solution?
A dynamic equilibrium is established in a solution when particles return to the surface of the solid at the same rate as they are leaving.
When you put salt in water, particles leave its surface, and it goes into solution (dissolves). However, you can add so much salt that it will not all dissolve. You then have a saturated solution.
When you have reached the saturation point, the dissolving process does not really stop. What happens is that particles are returning to the surface of the salt at the same rate as they are leaving.
The amount of material that is dissolving balances the amount of material that is crystallizing. We call this kind of balance a dynamic equilibrium.
You can see an excellent simulation of this dynamic equilibrium (requires Java!) at