Question

The formula of the complex, tris- (ethylenediamine) cobalt (iii) sulphate is:

• A. $\left[Co\right(en{)}_{2}S{O}_4]$
• B. $\left[Co\right(en{)}_{3}S{O}_4]$
• C. $\left[Co\right(en{)}_3{]}_2(S{O}_4{)}_3$
• D. $\left[Co\right(en{)}_3{]}_{2}S{O}_4$

Answer 1

The correct option is C $\left[Co\right(en{)}_3{]}_2(S{O}_4{)}_3$

${\left[CO{\left(en\right)}_3\right]}_2{\left({SO}_4\right)}_3$

$\to$ Oxidation of $en=0$ ${SO}_4=-2$ then we get $CO=+3$ as given

$\to$ And tris is used as two numbers are present at that same spot.

$\to$ where $2$ is called $"di"$ and $3$ is called $"tris"$.

Ans :- Option C.