Conditional Constants, Parasitic Reaction Coefficients, and Apparent Concentrations

2 Conditional Constants, Parasitic Reaction Coefficients, and Apparent Concentrations 

Using conditional constants permits us easily and rapidly to quantitatively predict the course of complexes formation reactions that would occur in the experimental conditions depicted in the previous section. However, the prediction can be performed only at the cost of some approximations, which can be legitimized. 

The underlying principle of the conditional constant concept is that in analysis, the concentration of utmost importance is that of the anticipated complex, and not necessarily that of any other species in the reaction vessel. 

Let [M] be the total concentration of the metallic ion for whatever species it is engaged in except for the exact complex in which we want to engage it and also the hydroxylated or protonated forms of this complex that is. 

Let s call [EDTA] the total H4EDTA concentration (tetraacid and its anions) except for the concentration of the complex under study  

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