Give evidence that `[Co(NH_(3))_(5)Cl]SO_(4) and [Co(NH_(3))_(5)SO_(4)]Cl` are ionization isomers.

Explanation

We dissolve both the compounds in water in separate test tubes. To the both test tube I Step or I Test: Add `BaCl_(2)` solution One compound give white ppt., indicating the presence of `SO_(4)^(2-)` ions.
The other compound does not give white ppt, indicating the absence of `SO_(4)^(2-)`ions.
`underset("[I]")([Co(NH_(3))_(5)Cl])SO_(4)+BaCl_(2)(aq) rarr [Co(NH_(3))_(5)Cl]Cl_(2)+underset("White ppt")(BaSO_(4)(s))`
`underset("[II]")([Co(NH_(3))_(5)SO_(4)])Cl+BaCl_(2)(aq) rarr" No reaction "`
II Test : Add `AgNO_(3)` solution to both the compounds in separate test tubes :
Only [II] compound gives white ppt, not the [I] one, due to absence `Cl^(-)` as counter ion.
`underset("[II]")([Co(NH_(3))_(5)SO_(4)])Cl+AgNO_(3)(aq) rarr[Co(NH_(3))_(5)SO_(4)]NO_(3)+underset("White ppt")(AgCl(s))`
`[Co(NH_(3))_(5)Cl]SO_(4)+AgNO_(3)(aq) rarr" No reaction "`
These two tests prove that the given two compounds are a pair of ionization isomers.