Question

The IUPAC name of $\left[Co{\left({NH}_3\right)}_6\right]\left[Cr{\left(C_2{O}_4\right)}_3\right]$ is__________.

• A. Hexaamminecobalt (III) tris (Oxalato) chromate (III)
• B. Hexaamminecobalt (III) tris (Oxalato) chromium (III)
• C. Hexaamminecobalt (II) tris (Oxalato) chromium (III)
• D. Hexaamminecobalt (III) trisoxalatochromate (III)

Answer 1

Answer: (A)

Hexaamminecobalt (III) tris (Oxalato) chromate (III)

The complex exists as $\left[Co\right(N{H}_3{)}_6{]}^{3+}\left[Cr\right(C_2{O}_4{)}_3{]}^{3-}$

and named as ${}^{\prime }Hexaamminecobalt\left(III\right)tris\left(oxalato\right)chromate\left(III\right)$

Metal having a cation complex is named first followed by anionic complex.

Hence, option (A) is correct.