Question

One mole of the complex compound $Co(N{H}_3{)}_{5}C{l}_3$ gives three moles of ions on dissolution in water. One mole of the same complex reacts with two moles of $AgN{O}_3$ solution to yield two moles of $AgCl\left(s\right)$. The structure of complex is:

• A. $\left[Co\right(N{H}_3{)}_{4}Cl]C{l}_2.N{H}_3$
• B. $\left[Co\right(N{H}_3{)}_{5}Cl]C{l}_2$
• C. $\left[Co\right(N{H}_3{)}_{3}C{l}_3].2N{H}_3$
• D. $\left[Co\right(N{H}_3{)}_{4}C{l}_2]Cl.N{H}_3$

Answer 1

The correct option is B $\left[Co\right(N{H}_3{)}_{5}Cl]C{l}_2$

$Co(N{H}_3{)}_{5}C{l}_3$ gives three ions - one complex ion and two chloride ion which is confirmed by reaction with silver nitrate.

$2AgN{O}_3+2C{l}^{-}\to 2AgCl$

On disolving in water:

$\left[Co\right(N{H}_3{)}_{5}Cl]C{l}_2⟶[Co(N{H}_3{)}_{5}Cl{]}^{2+}+2C{l}^{-}$

So, compound is $\left[Co\right(N{H}_3{)}_{5}Cl]C{l}_2$.