Ethylenediaminetetraacetic acid [(HOOC- CH₂)₂N-CH₂- CH₂-N(CH₂-COOH)₂], typically shortened to EDTA, is a chemical compound with the ability to form multiple bonds with metal ions, making it an important chemical to analytical scientists and industry alike.

The compounds used to create EDTA include ethylenediamine, formaldehyde and sodium cyanide. When these compounds are mixed in an appropriate fashion, a series of chemical reactions take place. Formaldehyde reacts with the sodium cyanide to form formaldehyde cyanohydrin. In the presence of sulfuric acid, this compound then reacts with ethylenediamine forming an intermediate compound that eventually reacts with water to form EDTA.

Solid EDTA is readily dissolved in water where it can form multiple chemical bonds with many metal ions in a solution, in effect tying up the metal ions. A molecule such as EDTA that has at least one free pair of unbonded electrons and therefore...