What is the chelate effect?

A) The reaction of en or dien with the hexaaquaniclel (II) cation as results in replacement of the water molecules with the nitrogen-based ligands.
B) The name of experiment 23
C) The phenomenon of greater equilibrium constants for the reaction of chelating ligands versus non-chelating ligands.

The phenomenon of greater equilibrium constants for the reaction of chelating ligands versus non-chelating ligands.

Explanation:

The chelate effect is defined as  the augmented affinity of chelating ligands for any mettalic ion in comparison of the affinity of a similar nonchelating ligands for the same metallic ion.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.