what is complexometric titration
Complexometric titration (sometimes chelatometry) is a form of volumetric analysis in which the formation of a colored complex is used to indicate the end point of a titration. Complexometric titrations are particularly useful for the determination of a mixture of different metal ions in solution.An indicator capable of producing an unambiguous color change is usually used to detect the end-point of the titration.DTA forms an octahedral complex with most 2+ metal cations, M 2+ , in aqueous solution. The main reason that EDTA is used so extensively in the standardization of metal cation solutions is that the formation constant for most metal cation-EDTA complexes is very high, meaning that the equilibrium for the reaction: