JEE Advanced 2016 · Paper 2 · Chemistry Q22

ChemistrySingle correct+3 / -1Question 22 of 54

The geometries of the ammonia complexes of $\ce{Ni^{2+}}$ , $\ce{Pt^{2+}}$ and $\ce{Zn^{2+}}$ , respectively, are

octahedral, square planar and tetrahedral

square planar, octahedral and tetrahedral

tetrahedral, square planar and octahedral

octahedral, tetrahedral and square planar

Answer and worked solution

Official answer: A

Ni²⁺ ( $d^8$ ) with NH₃ forms octahedral $\ce{[Ni(NH3)6]^{2+}}$ .
Pt²⁺ ( $5d^8$ ) forms square-planar $\ce{[Pt(NH3)4]^{2+}}$ (large crystal-field splitting).
Zn²⁺ ( $d^{10}$ ) forms tetrahedral $\ce{[Zn(NH3)4]^{2+}}$ .

(A)

Topics:Valence bond theory Crystal field theory

JEE Advanced 2016 · Paper 2, Chemistry question 22