Question

A coordination compound X gives pale yellow colour with $AgN{O}_3$ solution while its isomer Y gives white precipitate with $BaC{l}_2$. Two compounds are isomers of $CoBrS{O}_4$.$5N{H}_3$. What could be the possible formula of X and Y?

• A. $X=\left[Co\right(N{H}_3{)}_{5}S{O}_4]Br,Y=[Co\left(N{H}_3{)}_{5}Br\right]S{O}_4$
• B. $X=\left[Co\right(N{H}_3{)}_{5}Br]S{O}_4,Y=[Co\left(N{H}_3{)}_{5}S{O}_4\right]Br$
• C. $X=\left[Co\right(N{H}_3{)}_{5}Br\left(S{O}_4\right)],Y=[CoBr\left(S{O}_4\right)\left(N{H}_3{)}_5\right]$
• D. $X=\left[Co\right(Br{)}_{5}N{H}_3]S{O}_4,Y=[CoBr\left(S{O}_4\right)]N{H}_3$

Answer 1

The correct option is A $X=\left[Co\right(N{H}_3{)}_{5}S{O}_4]Br,Y=[Co\left(N{H}_3{)}_{5}Br\right]S{O}_4$

$\left[Co\right(N{H}_3{)}_{5}S{O}_4]Br$ will dissociate to give bromide ions. On reaction with silver nitrate, pale yellow precipitate of silver bromide will be obtained.

$\left[Co\right(N{H}_3{)}_{5}S{O}_4]Br\to [Co(N{H}_3{)}_{5}S{O}_4{]}^{+}+B{r}^{-}$

$\left[Co\right(N{H}_3{)}_{5}Br]S{O}_4$ will dissociate to give sulphate ions. On reaction with barium chloride, a white precipitate of barium sulphate will be obtained.

$\left[Co\right(N{H}_3{)}_{5}Br]S{O}_4\to [Co(N{H}_3{)}_{5}Br{]}^{2+}+S{O}_4^{2-}$