Mixture $X$ containing 0.02 mol of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{SO}_{4

Question

Mixture $X$ containing 0.02 mol of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}ight)_{5} \mathrm{SO}_{4}ight]$ Br and 0.02 mol of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}ight)_{5} \mathrm{Br}ight] \mathrm{SO}_{4}$ was prepared in 2 litre of solution.\ 1 litre of mixture $X+$ excess $\mathrm{AgNO}_{3} ightarrow Y$\ 1 litre of mixture $X+$ excess $\mathrm{BaCl}_{2} ightarrow Z$\ No. of moles of $Y$ and $Z$ are\

Professor PC Thomas Classes · Answer

(a): Number of moles of $\mathrm{Br}^{-}$in the mixture $=0.02 / 2 \mathrm{~mol}=0.01 \mathrm{~mol} / \mathrm{L}$\ $\left\{\mathrm{Br}^{-}ight.$ions are produced in case of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}ight)_{5} \mathrm{SO}_{4}ight] \mathrm{Br}$ only and not in case of $\left.\left[\mathrm{Co}\left(\mathrm{NH}_{3}ight)_{5} \mathrm{Br}ight] \mathrm{SO}_{4}ight\}$\ Number of moles of $\mathrm{SO}_{4}^{2-}$ in the mixture $=0.02 / 2=0.01 \mathrm{~mol} / \mathrm{L}$\ $\left\{\mathrm{SO}_{4}^{2-}ight.$ ions are produced in case of $\left[\mathrm{Co}\left(\mathrm{NH}_{3}ight)_{5} \mathrm{Br}ight] \mathrm{SO}_{4}$ only $\}$\ Now\ 1 litre of mixture + Excess $\mathrm{AgNO}_{3} ightarrow Y$ $$ \underset{0.01}{\mathrm{Br}^{-}}+\underset{	ext { Excess }}{\mathrm{Ag}^{+}} ightarrow \underset{0.01}{\mathrm{AgBr}} $$ $	herefore \quad Y=0.01$\ Also 1 litre of mixture + Excess $\mathrm{BaCl}_{2} ightarrow Z$ $$ \underset{	ext { Excess }}{\mathrm{SO}_{4}^{2-}}+\underset{0.01}{\mathrm{Ba}^{2+}} ightarrow \underset{	ext { ExaSO }}{\mathrm{BaSO}_{4}} $$ $	herefore \quad Z=0.01$\