Question

Magnetic moment of ${\left[Ni(CN{)}_4\right]}^{2-}$ is zero but that of ${\left[Ni{\left(H_{2}O\right)}_4\right]}^{2+}$ is $2.83BM$ It is because of

• A. Different oxidation state of $Ni$ in two complexes
• B. $C{N}^{-}$is a strong ligand making two unpaired electrons in $N{i}^{2+}$ paired while in ${\left[N{i}_2{\left(H_{2}O\right)}_4\right]}^{2+}$, two electrons remain unpaired $H_{2}O$ being weak ligand
• C. Both (a) and (b)
• D. None of the above

Answer 1

Answer: (B)

Correct answer is (b) $C{N}^{-}$is a strong ligand making two unpaired electrons in $N{i}^{2+}$ paired while in ${\left[N{i}_2{\left(H_{2}O\right)}_4\right]}^{2+}$, two electrons remain unpaired $H_{2}O$ being weak ligand