What type of ligand is the oxalate ion?

Identify the type of hybridization present in $\left[\mathrm{Ni}(\mathrm{CN})_4\right]^{2-}$.

What is the number of unpaired electrons present in $\left[\mathrm{CoF}_6\right]^{3-} ?$

What is the number of moles of ionisable $\mathrm{Cl^-}$ ions in a coordinate complex if it forms two moles of $\mathrm{AgCl}$ when treated with silver nitrate solution in excess?