Question:
The number of stereoisomers possible for $\left[\mathrm{Co}(\mathrm{O} \mathrm{x})_{2}(\mathrm{Br})\left(\mathrm{NH}_{3}\right)\right]^{2-}$ is$[\mathrm{O} \mathrm{x}=$ oxalate $]$
Solution:
(3)
Total stereoisomer $=2(\mathrm{OI})+1 \mathrm{POE}$ (pair of enantiomers) $=3$