When given a chemical formula, how can you determine the charge on a transition metal?
Look at its anion companion's charge(s) and go from there.
You can determine the charge of a transition metal by looking at its anion (negatively charged ion) partner.
For example, lets say you are given
You know that
Therefore, we can set up an equation with the given information to find
Charge of transition metal + Charge of anion partner = Total charge of compound
Therefore, the charge of the transition metal for this example is
You can use the given principle and bolded equation for pretty much any case where you are asked to find the charge of the transition metal. Just remember that if you have a compound like
I hope that helps!