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?

Identify a complex having monodentate ligand from following :

What type of isomerism is exhibited by $\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right] \mathrm{Cl}_3$ and $\left[\mathrm{Cr}\left(\mathrm{H}_2 \mathrm{O}\right)_5 \mathrm{Cl}\right] \mathrm{Cl}_2 \cdot \mathrm{H}_2 \mathrm{O}$