Question

Which of the following has a shape different from others? 

(a)  [Zn(NH₃)₄]⁺² 

(b)  Ni(CO)₄

(c)  [Cd(CN)₄]^-2 

(d)  [Cu(NH₃)₄]⁺²

Answer 1

Correct option   (d) [Cu(NH₃)₄]⁺²

Explanation:

[Zn(NH₃)₄]²⁺, Ni(CO)₄ & [Cd(CN)₄]^2– all form tetrahedral structures where the central atom uses sp3 hybridisation.

Whereas [Cu(NH₃)₄]²⁺ uses dsp² hybridisation and forms square planar structure. Although Cu should use both tetrahedral (sp³) & square planar (dsp²) hybridisations but the later one is confirmed through X-ray analysis.