Which of the following are paramagnetic?
A. $\left[\mathrm{NiCl}_4\right]^{2-}$
B. $\mathrm{Ni}(\m

Question

Which of the following are paramagnetic? 
A. $\left[\mathrm{NiCl}_4\right]^{2-}$ 
B. $\mathrm{Ni}(\mathrm{CO})_4$ 
C. $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{2-}$ 
D. $\left[\mathrm{Ni}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}$ 
E. $\mathrm{Ni}\left(\mathrm{PPh}_3\right)_4$ 
Choose the correct answer from the options given below:

Professor PC Thomas Classes · Answer

(a) : (A) In $\left[\mathrm{NiCl}_4\right]^{2-}$, there are two unpaired electrons because $\mathrm{Cl}^{-}$is a weak field ligand. Therefore, it is paramagnetic in nature.