Question

The geometry and magnetic behaviour of the complex $[Ni(CO)_4]$ are

• A. tetrahedral geometry and paramagnetic
• B. square planar geometry and diamagnetic
• C. square planar geometry and paramagnetic
• D. tetrahedral geometry and diamagnetic

Answer 1

Answer: (D)

tetrahedral geometry and diamagnetic

Answer 2

$Ni (28):[ Ar ] 3 d ^{8} 4 s ^{2}$
$\because CO$ is a strong field ligand

Configuration would be :

For, four $'CO'$ -ligands hybridisation would be $sp ^{3}$ and thus the complex would be diamagnetic and of tetrahedral geometry.