$[Co(C_2O_4)_3]^{3-}$ is a :

$EDTA^{4-}$ is the ethylenediaminetetraacetate ion. The total number of $N-Co-O$ bond angles in the $[Co(EDTA)]^{-}$ complex ion is:

Match the hybridisation in Column $I$ with the complexes in Column $II$. The options represent the matches for $(A), (B), (C), (D)$ respectively.

Column $I$	Column $II$
$(A)$ $sp^3$	$(i)$ $[Co(NH_3)_6]^{3+}$
$(B)$ $dsp^2$	$(ii)$ $[Ni(CO)_4]$
$(C)$ $sp^3d^2$	$(iii)$ $[Pt(NH_3)_2Cl_2]$
$(D)$ $d^2sp^3$	$(iv)$ $[CoF_6]^{3-}$
	$(v)$ $[Fe(CO)_5]$

Geometrical shapes of the complexes formed by the reaction of $Ni^{2+}$ with $Cl^{-}$,$CN^{-}$,and $H_2O$,respectively,are

The metal $Ni$ $(Z = 28)$ combines with a unidentate ligand $X^-$ to form a paramagnetic complex $[NiX_4]^{2-}$. What are its geometry and the number of unpaired electrons in $Ni$?

Consider the reaction $K_2[Ni(CN)_4] + 4K + 4NH_3 \to A$ (complex $A$).
Complex $A$ gives five ions in aqueous solution. Choose the $CORRECT$ statements.