Question

Of the following complex ions which is diamagnetic in nature?

• A. $[Ni(CN{)}_4{]}^{2-}$
• B. $[CuC{l}_4{]}^{2-}$
• C. $[Co{F}_6{]}^{3-}$
• D. $[NiC{l}_4{]}^{2-}$

Answer 1

Answer: (A)

${\left[Ni(CN{)}_4\right]}^{2+}$ has $d^8(Ni,2+)$ which undergoes pairing to give (refer to image) dsp ${}^2$ hybridisation and no unpaired electron so diamagnetic.