QuestionCoordination / geometry and magnetism
The complex ions [NiCl₄]²⁻ and [Ni(CN)₄]²⁻ are:
- (a) Both square planar
- (b) Both diamagnetic
- (c) Both paramagnetic
- (d) Paramagnetic and diamagnetic respectively
Answer: (d) Paramagnetic and diamagnetic respectively
[NiCl₄]²⁻: Cl⁻ weak, sp³ tetrahedral, 2 unpaired e⁻ → paramagnetic. [Ni(CN)₄]²⁻: CN⁻ strong, pairs electrons, dsp² square planar → diamagnetic → (d).