Do It with a Spreadsheet

Consider the titration of metal ion M (concentration = Cm. initial volume = V7nl) with a solution of ligand L (concentration = Ch volume added = V,) to form a 1 1 complex  

Substituting /fr[M][L] (from Equation 12-8) for [ML] in the mass balances gives 

Now substitute the expression for [L] from Equation 12-10 back into Equation 12-9 

Total ligand concentration moles of ligand added total volume C,V, 

If you reverse the process and titrate ligand with metal ion, the fraction of the way to the equivalence point is the inverse of the fraction in Equation 12-11  

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