Which of the following is a hexadentate ligand ?

Options

A. Ethylenediaminetetraacetato
B. Dimethylglyoxime anion
C. 8- Hydroxyquinolinol ion
D. 2,2' - Dipyridyl

Answer

A

Explanation

Ethylene diamineteracetate ion, `(EDTA)^(4-)` , is a ligand that bonds through six of its atoms. It bonds through two N atom and four O atoms to the metal and so forms five rings. Because of the stabilitity of chelates, polydentate ligands (aso called chelating agents) are often used to remove metal ions form a chemical system. For example, EDTA is added to certin canned foods to remove transition-metal ions that can catalyze the ddeterioration of the food. The same chelating agent has been used to treat lead poisoning because it binds `Pb^(2+)` ions as the chelat, which can then be excreated by the kidneys.