A coordination compound of cobalt has the molecular, formula containing five ammonia molecules, one nitro group and two chlorine atoms for onew cobalt atom. One mole of this compounds three ions in an aqueous solution. On reacting this solution with excess of `AgNO_(3)` solution, we get two moles of AgCI precipitate. The ionic formula for this complex would be

Options

A. `[Co(NH_(3))_(5) (NO_(2))] CI_(2)`
B. `[Co(NH_(3))_(5)CI][CI(NO_(2))]`
C. `[Co(NH_(3))_(4)(NO_(2))CI][NH_(3))CI]`
D. `[Co(NH_(3))_(5)][(NO_(2))_(2)CI_(2)]`

Answer

A

Explanation

The two C1 atoms must be outside the coordination sphere so as yield two moles of AgC1 precipitate per mole of complex.
`[Co(NH_(3))_(5)(NO_(2))]C1_(2) overset (H_(2)O) rarr [Co(NH_(3))_(5)(NO_(2))]^(2+) + 2C1^(-)`
`2C1^(-) overset (AgNO_(3)) underset (excess) rarr 2AgC1 (s)`