Chemistry - Coordination Chemistry Question with Solution | TestHub

(A) Correct: $[NiC{l}_4{]}^{2-}$ has 2 unpaired electrons ($s{p}^3$, $d^8$) and O₂ has 2 unpaired electrons (${\pi }^{\ast }$ MOs), totaling 4.

(B) Correct: $[Ni(en{)}_2(N{H}_3{)}_2{]}^{2+}$ has 3 stereoisomers (cis- $d/l$ + trans) and $[Ni(Gly{)}_3{]}^{-}$ has 4 (fac- $d/l$ + mer- $d/l$), totaling 7.

(C) Correct: H₃PO₃ has 1 P-H bond and H₃PO₂ has 2 P-H bonds, giving a total of 3.

(D) Correct: Both $[Ni(CO{)}_4]$ and $[Fe(CO{)}_4{]}^{2-}$ are 18-electron complexes, so the total valence electrons around the metals are $18+18=36$.