First of all, thank you for your time! However, We are not taught about the method with the Lewis structures.
We are taught to determine the oxidation number using rules such as:
-For nonbinary ionic compounds, assign the mteal first then work on the polyatomic ion.
-In compounds that have a nonmetal and a transition metal, assign the nonmetal its "normal" oxidation number then assign the oxidation number to the transition metal to make a sum of zero or the charge on an ion
-The oxidation number of F in any compound is –1
That's why I don't get question a and b!
For Au(NO3)3, I don't know how to assign oxidation number for Au first(it's a transition metal)..Someone told me that "becuase NO3 in the formula has a charge of 1-, then (NO3)3 has a charge of 3-, to balance out, Au should have an oxidation number of +3"..WHY? Are oxidation numbers AND electric charges related?
For NaN3, will the oxidation number for N be -1/3 (a fraction)?
Thanks for your *delete me*