question_answer

The geometry and magnetic behaviour of the complex \[\text{ }\!\![\!\!\text{ Ni(CO}{{\text{)}}_{\text{4}}}\text{ }\!\!]\!\!\text{ }\] are [NEET - 2018]

A)  Square planar geometry and paramagnetic

B)  Tetrahedral geometry and diamagnetic

C)  Square planar geometry and diamagnetic

D)  Tetrahedral geometry and paramagnetic

Correct Answer: B

Solution :

\[\text{Ni(28): }\!\![\!\!\text{ Ar }\!\!]\!\!\text{ 3}{{\text{d}}^{\text{8}}}\text{4}{{\text{s}}^{\text{2}}}\] \[\because \text{CO}\] is a strong field ligand Configuration would be : For, four ?CO?-ligands hybridisation would be \[\text{s}{{\text{p}}^{\text{3}}}\] and thus the complex would be diamagnetic and of tetrahedral geometry.