Achieve #6

[Albert Chen 1G]

Hi, I have been having trouble with this problem.
For each metal complex, give the coordination number for the metal species.
[Co(en)2(CO)2]Br
How would you find the coordination number?

[Ayaan_Ekram_2J]

Hello!

A coordination number corresponds to the number of ligands, ions, or molecules that bind to a central metal cation in a coordination complex. Therefore, we see that there are four ligands bound to the central cobalt atom. However, en is polydentate and can bind in two places. Therefore, the coordination number for this coordination complex is 6 as en binds in a total of 4 places and the two CO molecules bind in a total of two places. I hope this helps!

[Kayley Steele 3D]

En is bidentate ligand and therefore can bind twice to the central atom Cobalt. There are two of this ligand and therefore 4 bonds of En to Co. The second ligand is Co which is monodentate and can only bind once. Since there are two then CO forms 2 bonds with the central atom. The coordination number is 6 because 4+2=6 and there are 6 bonds to the central atom.