Chemistry - Coordination Chemistry Question with Solution | TestHub

How many of the following are optically inactive?
i.$\mathrm{t}\mathrm{r}\mathrm{a}\mathrm{n}\mathrm{s}-{\left[\text{Co}{\left(\text{en}\right)}_2\left({\text{NH}}_3\right)\text{Cl}\right]}^{2+}$
ii.$\mathrm{c}\mathrm{i}\mathrm{s}-{\left[\text{Co}{\left(\text{en}\right)}_2{\text{Br}}_2\right]}^{+}$
iii.$\left[\text{Co}{\left({\text{NH}}_3\right)}_3{\text{Cl}}_3\right]$
iv.$\mathrm{t}\mathrm{r}\mathrm{a}\mathrm{n}\mathrm{s}-{\left[\text{Co}{\left({\text{NH}}_3\right)}_4{\text{Cl}}_2\right]}^{+}$
v.$\mathrm{t}\mathrm{r}\mathrm{a}\mathrm{n}\mathrm{s}-{\left[{\text{CoCl}}_2{\left({\text{C}}_2{\text{O}}_4\right)}_2\right]}^{3-}$