The joining of elements (e.g., chemical contaminants) with other elements or compounds, generally rendering them less available for uptake by living organisms.

formation of a structure or complex made up of ions and molecules and obtained using extractant systems and species to be extracted

a reaction in which a metal ion and one or more anionic ligands chemically bond. Complexes often prevent the precipitation of metals.

The ionic bonding of one or more central ions or molecules by one or more surrounding ions or molecules.

The formation of complex chemical species by the coordination of groups of atoms termed ligands to a central ion, commonly a metal ion. Generally, the ligand coordinates by providing a pair of electrons that forms an ionic or covalent bond to the central ion. See also chelate, coordination compound, and ligand.

A water treatment that involves adding certain chemicals to water to prevent any iron in it from oxidizing and changing the water's colour.

The inactivation of an ion by addition of a reagent that combines with it and, in effect, prevents it from participating in other reactions. Complexation is also call sequestration.