Displacement titration
A titration in which the analyte displaces a species, usually from a complex, and the amount of the displaced species is determined by a titration. [c.275]A second ligand in a complexation titration that initially binds with the analyte but is displaced by the titrant. [c.316]
Ca + if a small amount of Mg -EDTA is added to the solution containing the analyte. The Mg + is displaced from the EDTA by Ca +, freeing the Mg + to form the red Mg -indicator complex. After all the Ca + has been titrated, Mg + is displaced from the Mg -indicator complex by EDTA, signaling the end point by the presence of the uncomplexed indicator s blue form. [c.324]
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Stoichiometry > Back titration
The technique of back titration is used when the unknown compound cannot be dissolved in water for normal titration. The compound can however react with an acid, neutralising some of it. The remaining acid may then be titrated in the usual manner.
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