Amongst Ni ( CO )_4 , [ Ni (CN) _4 ]^ 2 - and [NiC l_4 ]^ 2 -

MCQ

Amongst $Ni{\left( {CO} \right)_4},$ ${\left[ {Ni{{(CN)}_4}} \right]^{2 - }}$ and ${[NiC{l_4}]^{2 - }}$

A
$Ni{\left( {CO} \right)_4}$ and ${\left[ {NiC{l_4}} \right]^{2 - }}$are diamagnetic and ${[Ni{(CN)_4}]^{2 - }}$ is paramagnetic
B
${\left[ {NiC{l_4}} \right]^{2 - }}$ and ${\left[ {Ni{{\left( {CN} \right)}_4}} \right]^{2 - }}$ are diamagnetic and $Ni{\left( {CO} \right)_4}$ is paramagnetic
✓
$Ni{\left( {CO} \right)_4}$ and ${\left[ {Ni{{\left( {CN} \right)}_4}} \right]^{2 - }}$ are diamagnetic and ${\left[ {NiC{l_4}} \right]^{2 - }}$ is paramagnetic
D
$Ni{\left( {CO} \right)_4}$ is diamagnetic and ${\left[ {NiC{l_4}} \right]^{2 - }}$ and ${\left[ {Ni{{\left( {CN} \right)}_4}} \right]^{2 - }}$ are paramagnetic

✓

Answer

Correct option: C.

$Ni{\left( {CO} \right)_4}$ and ${\left[ {Ni{{\left( {CN} \right)}_4}} \right]^{2 - }}$ are diamagnetic and ${\left[ {NiC{l_4}} \right]^{2 - }}$ is paramagnetic

c
(c) The electronic configuration of $Ni$ in
${[Ni{(CN)_4}]^{2 - }},\,{[Ni(C{l_4})]^{2 - }}$ and $Ni{(CO)_4}$ are as following
$CO$ and $C{N^ - }$ are strong ligands so they induces pairing of electrons so their complexes are diamagnetic while $C{l^ - }$ is a weak ligand so it does not induce the pairing of electrons so its complex is paramagnetic.