Coordination Compound 6th edition

Karina Vasquez 1D
Posts: 35
Joined: Fri Mar 01, 2019 12:15 am

Coordination Compound 6th edition

17.29 Name each of the following complex ions and determine the oxidation number of the metal: (a) [Fe(CN)6]^4-; (b) [Co(NH3)6]^3+; (c) [Co(CN)5(OH2)]^-2; (d) [Co(SO4)(NH3)5]^+.

Can someone explain how to solve this problem step-by-step?

Chem_Mod
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Re: Coordination Compound 6th edition

Consider (a) [Fe(CN)6]^4-.The first thing you want to do is identify the ligands and the transition metal atom. In this case, the ligand is CN- (it is a negatively charged ligand) and the metal is Fe (oxidation state will be found in the following steps). Now we know that there are 6 CN- so their charge will be -1 (6) = -6 The oxidation state is generally found by using the formula x + -1(6) = -4. We get x = +2 which will be the oxidation state of the metal (Fe^2+). Since we only have 1 type of ligand, naming is fairly straight forward. We look at the number of ligands (here 6) and prefix it to the ligands actual name --> hexacyano. While naming the metal we have to take into account that the metal is part of a complex which is overall negatively charged, thus we will attach ate as a suffix to the metal. So it will be ferrate (II) --> the (II) indicated the oxidation state of Fe metal. Now we combine the two and it gives hexacyanoferrate (II) which is the name of the compound. Others can be done in a similar manner. Please do post any follow-up questions that you may have.

Bella Martin
Posts: 47
Joined: Wed Sep 21, 2016 2:57 pm

Re: Coordination Compound 6th edition

Hi,
I'm having trouble with question 37, could someone explain the general rule for figuring out coordination numbers to compounds that are a bit difficult to write lewis structures for?