Question

The sum of coordination number and oxidation number of the metal $M$ in the complex $\left[M\right(en{)}_2\left(C_2{O}_4\right)]Cl$ (where en is ethylenediamine) is:

• A. $7$
• B. $8$
• C. $9$
• D. $6$

Answer 1

Answer: (C)

$9$

The sum of coordination number and oxidation number of the metal M in the complex $\left[M\right(en{)}_2\left(C_2{O}_4\right)]Cl$ (where en is ethylenediamine) is 9. The coordination number is 6 as $en$ and $C_2{O}_4$ are bidentate ligands.

Let $X$ be the oxidation number of $M$.

$X+2\left(0\right)-2=+1$

$X=+3$

Thus, the oxidation number is $3$.

Hence, the sum of coordination number and oxidation number of the metal M is $6+3=9$.