Concept #1: In these types of titration the ligand will serve as the titrant.
Concept #2: Before the equivalence point is reached we have an excess of the metal ion remaining.
Concept #3: At the equivalence point there are equal moles of the metal ion and the EDTA ligand.
Concept #4: Beyond the equivalence point there is an excess of the EDTA ligand remaining.
Example #1: Calculate the pMn3+ for the titration of 30.0 mL of 0.0100 M EDTA with 50.0 mL of 0.0200 M MnPO4 at pH = 10.00.
Practice: Calculate the pNi2+ for the titration of 50.0 mL of 0.120 M EDTA with 15.0 mL of 0.100 M NiCl2 at pH = 8.22.