Question

Amongst $[NiC{l}_4{]}^{2-},[Ni(H_{2}O{)}_6{]}^{2+},[Ni\left(PP{h}_3{)}_{2}C{l}_2\right],\left[Ni\right(CO{)}_4]$ and $\left[Ni\right(CN{)}_4{]}^{2-}$, the paramagnetic species are :

• A. $[NiC{l}_4{]}^{2-},[Ni(H_{2}o{)}_6{]}^{2+},[Nic{l}_4{]}^{2+},\left[Ni\right(PP{h}_3{)}_{2}C{l}_2]$
• B. $\left[Ni\right(CO{)}_4],[Ni\left(PP{h}_3{)}_2\right],[NiC{l}_4{]}^{2-}$
• C. $\left[Ni\right(CN{)}_4{]}^{2-},\left[Ni\right(H_{2}O{)}_6{]}^{2+},[NiC{l}_4{]}^{2-}$
• D. $\left[Ni\right(PP{h}_3{)}_{2}C{l}_2],[Ni\left(CO{)}_4\right],\left[Ni\right(CN{)}_4{]}^{2-}$

Answer 1

Answer: (A)

$[NiC{l}_4{]}^{2-},[Ni(H_{2}o{)}_6{]}^{2+},[Nic{l}_4{]}^{2+},\left[Ni\right(PP{h}_3{)}_{2}C{l}_2]$

The paramagnetic species are $[NiC{l}_4{]}^{2-},[Ni(H_{2}O{)}_6{]}^{2+},[Ni(C{N}^{-}{)}_4{]}^{2-},[Ni\left(PP{h}_3{)}_{2}C{l}_2\right]$
Outer electronic configuration $N{i}^{+2}=3d^{s}4s^0$ shows 2 unpaired electrons. Hence is paramagnetic.