Correct formula of the compound which gives a white precipitate with BaCl2 solution, but not with AgNO3 solution, is :
Solution
Only the counter ions are replaced easily by other reagents. <br/><br/>$\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Br}\right] \mathrm{SO}_{4}+\mathrm{BaCl}_{2} \rightarrow\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{Br}\right] \mathrm{Cl}_{2}+\underset{\text{White ppt.}}{\mathrm{BaSO}_{4}{\downarrow}}$
<br/><br/>
White ppt. It does not have chloride ion as counter ion so it will not give white ppt with $\mathrm{AgNO}_{3}$.
About this question
Subject: Chemistry · Chapter: Coordination Compounds · Topic: Ligands and Coordination Number
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