Which complex among the following gives a white precipitate on treatment with an aqueous solution of barium chloride?

Options

A. `[Pt(NH_(3))_(4)Br_(2)]Cl_(2)`
B. `[Co(NH_(3))_(5)SO_(4)]NO_(2)`
C. `[Co(NH_(3))_(5)NO_(2)]SO_(4)`
D. `[Pt(NH_(3))_(4)Cl_(2)]Br_(2)`

Answer

C

Explanation

Among the given coordination compounds, `[Co(NH_(3))_(5)NO_(2)]SO_(4)` gives a white precipitate on treatment with an aqueous solution of barium chloride. This can be explained by the following reaction .
`[Co(NH_(3))_(5)NO_(2)]SO_(4)+BaCl_(2)(aqto[Co(NH_(3))_(5)NO_(2)]Cl_(2)+underset("White ppt.")(BaSO_(4)(s))`
The other given compounds do not give white ppt. due to absence of `SO_(4)^(2-)` ions.