Ligands

[Alex Hitti 3E]

How do you find the oxidation state of transition metals in a coordination compound?

[Clarice Chui 2C]

In order to find the oxidation state of a transition metal, find the charges of the atoms around the central atom. Whatever those charges add up to, subtract that from the formal charge of the molecule as a whole. So for example if the formal charge of the molecule was neutral and the surrounding atoms’ charges added up to -2, then you know the oxidation state of the transition metal must be +2.

[NRobbins_1K]

First, look at the overall charge of the compound. Whatever it is, the negative charges of the ions and the positive charges of the transition metal must add to that overall charge. If the overall molecule is neutral, but there are two ligands with a charge of -1 each, then the oxidation state of the transition metal must be +2 so that the total -2 charge of the ligands are cancelled out.

[KarineKim2L]

The ligands have a set charge, as do the ions. So for example, for [Co(NH3)5Cl]Cl (There are 5 NH3s), then you know that the oxidation number of Cobalt is 2+. NH3 is always neutral, and the total charge for the coordination compound should be +1 because the charge of Cl is -1. +2 of Cobalt minus 1 for the Cl results in +1 charge for the whole coordination compound.

[Alison Trinh 1E]

Can someone explain what exactly a ligand is?

[Sean Cheah 1E]

Can someone explain what exactly a ligand is?

In this context, a ligand refers to an electron-pair donor that forms one or more coordinate covalent bonds with a central metal ion.