Question

Illustrate chelates with a suitable example.

Answer 1

Ethylenediaminetetraacetic acid (EDTA) is an example of a chelate. It has the ability to form chelates with metal ions like calcium (Ca²⁺), magnesium (Mg²⁺), or iron (Fe²⁺).

The structure of EDTA consists of two amine groups and four carboxyl groups. These functional groups can donate electron pairs to form coordination bonds with a metal ion.

\[\begin{array}{cc}
\phantom{.}\ce{\underset{\bullet\bullet}{^-O}OCCH2}\phantom{........................}\ce{CH2CO\underset{\bullet\bullet}{O^-}}\phantom{.}\\
\phantom{.}\backslash\phantom{.....................}/\phantom{.}\\
\phantom{.}\ce{\overset{\bullet\bullet}{N}-CH2-CH2-\overset{\bullet\bullet}{N}}\phantom{.}\\
\phantom{.}/\phantom{.....................}\backslash\phantom{.}\\
\phantom{.}\ce{\underset{\bullet\bullet}{^-O}OCCH2}\phantom{.......................}\ce{CH2CO\underset{\bullet\bullet}{O^-}}\phantom{.}\\
\end{array}\]