Komplexometris

Komplexometris is a method of quantitative chemical analysis. It involves the use of complexing agents, which are substances that form soluble complexes with metal ions. Typically, these complexing agents are chelating agents, meaning they can bind to a metal ion at multiple points, forming stable ring structures. The most common chelating agent used in komplexometris is ethylenediaminetetraacetic acid (EDTA).

The principle behind komplexometris is that the chelating agent will react stoichiometrically with the metal ion to be determined. By measuring the amount of chelating agent required to completely complex all the metal ions present, the concentration of the metal ion can be calculated. This is often achieved through titration, where a solution of the chelating agent is added to a solution containing the metal ions until the reaction is complete.

To detect the endpoint of the titration, an indicator is usually employed. These indicators are substances that change color when all the metal ions have been complexed by the chelating agent. Alternatively, instrumental methods such as potentiometry can be used to monitor the progress of the reaction and determine the endpoint.

Komplexometris is a versatile technique and can be used to determine the concentration of a wide range of metal ions, including calcium, magnesium, zinc, and copper. It finds applications in various fields, such as water analysis, pharmaceutical quality control, and food chemistry. The accuracy of the method depends on factors like the stability of the metal-EDTA complex and the appropriate choice of indicator or detection method.