ABSTRACT
The equilibrium expression is denoted as the mass law. The equilibrium constant may have different names corresponding to application of the mass law on different reactions. Many equilibrium calculations are carried out for the same solution with a well-defined ionic strength. The double logarithmic presentation will be presented as an excellent tool to overview the processes that are very important in management of aquatic ecosystems as they are the chemical processes that determine the biological processes in the aquatic ecosystems. Water is in contact with suspended solid or sediment and the equilibrium between solid and water is therefore very important for the water quality. The rate of transfer will usually be proportional to the distance from equilibrium and dependent on the diffusion coefficient of the compounds and of the resistance at the boundary layer between the two spheres.
