The correct statement among the following is:
- [Ni(CN)4]2- and [NiCl4]2- are diamagnetic and Ni(CO)4 is paramagnetic.
- Ni(CO)4 is diamagnetic and [NiCl4]2- and [Ni(CN)4]2- are paramagnetic.
- Ni(CO)4 and [NiCl4]2- are diamagnetic and [Ni(CN)4]2- is paramagnetic.
- Ni(CO)4 and [Ni(CN)4]2- are diamagnetic and [NiCl4]2- is paramagnetic.
Answer
(4) Ni(CO)4 and [Ni(CN)4]2- are diamagnetic and [NiCl4]2- is paramagnetic.
Solution
Ni(CO)4: Ni(0), 3d8 4s2; strong field CO pairs all electrons into 3d ( 3d10), sp3, tetrahedral no unpaired electron, diamagnetic.
[Ni(CN)4]2-: Ni2+, 3d8; strong field CN- pairs the electrons, dsp2, square planar diamagnetic.
[NiCl4]2-: Ni2+, 3d8; weak field Cl- cannot pair the electrons, sp3, tetrahedral 2 unpaired electrons, paramagnetic.
Ni(CO)4 and [Ni(CN)4]2- are diamagnetic and [NiCl4]2- is paramagnetic.
Answer: (4)