Question

The species having tetrahedral shape is

• A. $\left[ PdCl _{4}\right]^{2-}$
• B. $\left[ Ni ( CN )_{4}\right]^{2-}$
• C. $\left. Pd ( CN )_{4}\right]^{3-}$
• D. $\left[ NiCl _{4}\right]^{2-}$

Answer 1

Answer: (D)

$\left[ NiCl _{4}\right]^{2-}$

Answer 2

$Ni (28)=3 d^{8} 4 s^{2}$ $Ni ^{2+}=3 d^{8} 4 s^{0}$ Here $XX$ represents electron pairs donated by $Cl ^{-}$ion. $\left[ NiCl _{4}\right]^{2-}$ shows paramagnetic characteristics due to the presence of two unpaired electrons. The $3 d$ orbitals remain undisturbed because $Cl ^{-}$ligand is weak field ligand therefore, $Ni ^{2+}$ ion undergoes $s p^{3}$ hybridisation resulting in tetrahedral structure of the complex.