Question

Which of the following ligands would you choose to use to use if you needed to trap and then remove all of the metal ions from a sample of lake water?

Cl^- , OH^- , C5H5^-, EDTA, Bipy, and PCy₃

_{Also, please explain why you chose your answer.}

Answer 1

answer is EDTA

This hexadentate ligand forms very stable complexes (usually octahedral structures) with most of the transition metals. The donor atoms in EDTA^4- are the two N atoms, and the four, negatively charged O atoms.

EDTA^4- is used to "trap" trace amounts of transition metals that could potentially catalyze the decomposition of the product.

Several features of EDTA's complexes are relevant to its applications. First, because of its high denticity, this ligand has a high affinity for metal cations

EDTA chelation therapy is approved by the U.S. Food and Drug Administration (FDA) as a treatment for lead and heavy metal poisoning. It is also used as an emergency treatment for hypercalcemia (excessive calcium levels) and the control of ventricular arrhythmias (abnormal heart rhythms) associated with digitalis toxicity

The reduction of water hardness in laundry applications and the dissolution of scale in boilers both rely on EDTA and related complexants to bind Ca²⁺, Mg²⁺, as well as other metal ions. Once bound to EDTA, these metal centers tend not to form precipitates or to interfere with the action of the soaps and detergents. For similar reasons, cleaning solutions often contain EDTA.

Answer 2

C5H5