On So-Called Concentration and True Thermodynamic Equilibrium Constants in Solution

Advantages and disadvantages of the concentration and thermodynamic constants of equilibria in solution were compared. The standard state of a solute in solution with a finite ionic strength was shown to have practical advantages (as in biochemical thermodynamics where a solution with an ionic strength of 0.25 is referred to as a standard). It was suggested that a solution with a certain finite ionic strength can be used more widely as an informally (or even formally) adopted second standard state in solution thermodynamics.