Really unsure about these, any help would be great!
Pt^4+ with NH3 (Pt4+ has coordination number 6)
and then how to find coordination number from this formula,
[Ni(CN)4]^2
1 Answer

Coordination numbers is just the number of ligand atoms attached to the metal.
So for Pt^4+ with NH3 (Pt4+ has coordination number 6),
NH3 is the ligand so there’s 6 of them attached to Pt…
[Pt(NH3)6]^4+
since Pt is 4+ the overall charge of the complex is 4+ as (NH3)6 has a neutral charge.
For [Ni(CN)4]^2…
there are 4 CN’s so the coordination number is 4! If you want to find the oxidation number of nickel…
x + 4(1) = 2
x = +2
Hope that helps!