Keywords
Coordination compound
Number of coordination
Overall formation constant
Titration by precipitation
Lewis acids and bases
Solubility
Solubility product
Métricas
How to Cite
Abstract
In principle, a mononuclear coordination compound (also known as a complex) is an arrangement formed by the interaction of a central metal ion (or atom), referred to as the “core,” with surrounding atoms, ions, or molecules, called “ligands.” The number of ligands that form coordinate bonds is known as the coordination number, which depends on the electronic configuration of the central ion (or atom), its charge, and its size, among other factors. In this educational experiment, the goal is to determine the coordination number and the overall formation constant of the diamine-silver(I) complex using the precipitation titration technique. This can be achieved by calculating the concentrations of uncomplexed silver ions present in mixtures prepared with constant amounts of silver(I) ions and increasing amounts of ammonia. The remaining concentrations of [Ag⁺] ions in solution are determined through titration with a standardized bromide ion solution. Although the experimental procedure appears straightforward, it requires technical skills for the proper handling of basic laboratory instruments and knowledge of logarithmic functions. Furthermore, interpreting the results demands theoretical understanding of concepts such as Lewis acids and bases, solubility phenomena and solubility product, charge and mass balance, and complex formation constants. Processing experimental data and constructing graphs are essential skills.
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