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Q.
The correct IUPAC name for the compound $\left[ Co \left( NH _{3}\right)_{4} CI ( ONO )\right] Cl$ is:
Coordination Compounds
Solution:
In $\left[ Co \left( NH _{3}\right)_{4} Cl ( ONO )\right]^{+} Cl ^{-}$, cobalt is in $+3$ oxidation state
and the complex is cationic. ONO ligand attach to metal ion through $O$ atom; so $- O -$ is used while naming as nitrito before the name of metal ion. So IUPAC name given in option (D) is correct