Table of Contents
An introduction to Complexometric Titration
Complexometric titrations use a complexing agent to sequester one metal ion from another. The complexing agent is usually a weak acid or base, and the metal ions are usually strong acids or bases. The complexing agent forms a stable complex with one of the metal ions, and this complex can be titrated with a standard solution of the other metal ion. The concentration of the standard solution is known, so the concentration of the metal ion in the original sample can be calculated.
What is Complexometric Titration?
Complexometric titration is a type of titration in which the titrant and analyte form a complex. The complex can be either soluble or insoluble. The most common type of complexometric titration is called EDTA titration.
Complexometric Indicator
A complexometric indicator is a molecule that changes color in the presence of metal ions. The indicator forms a complex with the metal ion, and the complex has a different color than the individual indicator molecule. Complexometric indicators used to measure the concentration of metal ions in a solution.
Complexometric Titration using EDTA
A complexometric titration a titration performed using a chelating agent, such as ethylenediaminetetraacetic acid (EDTA). The EDTA forms complexes with metal ions, which can then titrated using a standard acid. The concentration of the metal ion in the sample can determined by measuring the endpoint of the titration.
Types of Complexometric Titration
There are a few different types of complexometric titration. The most common types are:
- Titration of a strong base with a weak acid
- Also titration of a weak base with a strong acid
- Titration of a weak acid with a strong base
Applications of Complexometric Titrations
There are a number of applications for complexometric titrations. One common application is in the determination of the concentration of a metal ion in a solution. This can done by titrating the solution with a complexing agent that forms a stable complex with the metal ion. The concentration of the metal ion can then determined by measuring the amount of complexing agent used in the titration.
Another application of complexometric titrations is in the determination of the concentration of a weak acid or a weak base in a solution. This can done by titrating the solution with a strong acid or a strong base, respectively. The concentration of the weak acid or base can then determined by measuring the amount of strong acid or base used in the titration.
