Oxidation Numbers

[Samantha Loc 1B]

How do you take into account the charges of elements outside of the coordination sphere (or brackets) when trying to find the oxidation number of transition metals?

[Mark_Botros_1D]

When finding the oxidation number, consider the charge of the elements outside by understanding the most common anions/cations these elements make.

[grace salvestrin 1J]

Just to add on^ for example, if the element outside the brackets has a charge of negative 2, and the coordination compound as a whole has a neutral charge, then the charge inside the brackets has to equal a positive 2. So if the charge inside the brackets is positive 2, you should assign a charge to the transition metal that will make bring the charge to +2.

[Raizel Ferrer 1H]

When trying to find the oxidation number, it is the overall charge - the ligand charges. For the transition metal, you would make that x in an equation and subtract the charges known inside of the bracket. Set that equation equal to the charge outside of the brackets and solve for x which solves for the oxidation number of the metal.

[Shriya_Amara_1G]

You would use the generic anion/cation charge that is associated with that element. For example, if Cl is attached to the complex, the complex would have a +1 charge, to make the overall coordination compound neutral.

[Nicole 3G]

Remember the overall coordination compound should be neutral. So the charge of the ion on the outside of the brackets should be equal and opposite to the charge of the inside.

With this information, set up an equation that looks like this: (Charge of TM) + (Charge of Ligands) + (Charge of outer ion) = 0

Fill in what you know (the ligand and the outer ion charges) and solve for the charge of the transition metal.