## FALL 2015 #4 [ENDORSED]

Michelle_Nguyen_3F
Posts: 40
Joined: Wed Sep 21, 2016 2:59 pm

### FALL 2015 #4

For the complex ions listed below, determine the oxidation state and the coordination number of the central metal ion?
$[Fe(Cl)_{4}(en)]^{-2^}$

I know that the oxidation state is +2, but I am confused on how to get the coordination number. I know that the number of bonds is equal to the coordination number. I thought the coordination number was 5, but I am incorrect. Could someone please explain why it is a different answer and how they came to that answer? Thank you!

Chem_Mod
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### Re: FALL 2015 #4  [ENDORSED]

Remember in class I discussed that en is the notation used for ethylenediamine and that ethylenediamine is bidentate and forms two bonds via the lone pair on each N atom.
ethylenediamine = 2 bonds
each Cl- = 1 bond

This results in 6 bonds and a coordination number of 6.