Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central atom. Usually these ligands are organic compounds, and are called chelants, chelators, chelating agents, or sequestering agents.
Chelation is useful in applications such as providing nutritional supplements, in chelation therapy to remove toxic metals from the body, as contrast agents in MRI scanning, in manufacturing using homogeneous catalysts, and in fertilizers.
The chelate effect is the enhanced affinity of chelating ligands for a metal ion compared to the affinity of a collection of similar nonchelating (monodentate) ligands for the same metal.
Consider the two equilibria, in aqueous solution, between the copper(II) ion, Cu2+ and ethylenediamine (en) on the one hand and methylamine, MeNH2 on the other.
In (1) the bidentate ligand ethylenediamine forms a chelate complex with the copper ion. Chelation results in the formation of a five-membered CuC2N2 ring. In (2) the bidentate ligand is replaced by two monodentate methylamine ligands of approximately the same donor power, meaning that the enthalpy of formation of Cu—N bonds is approximately the same in the two reactions.
A discontent for the vile and the wretched
Will bring forth reparations of the most severe degree
Things will change
And I will be the catalyst to
Weed out the weak and beget strength of character
Glorifying minds and souls
Celebrate the spirit while denying breath and life
To those who would choose to live depraved
Depravity, a thing of the past
A life not in vain
I am the end, I am beginning life anew
My soul is free from weakness
Free
Refined as gold
A standard to be met by all
As we embrace righteousness, we embrace life
Purified, united. set aside from the majority
I will serve as an example to man as hope
By defending those I love with my life
I stand here bold and strong
As a testament to my abstinence