Amongst the following complexes, (mentioned without any charge) how many of them are expected to have a `+vely` charged counter ion ?
`(a) [PtCl_(6)]" "(b) [Ni(NH_(3))_(4)]`
`(c ) [Fe(C_(2)O_(4))_(3)]" "(d) [Co(en)_(3)]`
`(e ) [Fe(CN)_(6)]" "(f) [PtCl_(4)]`
`(g) [Ni(CO)_(4)]" "(h) [Co(NH_(3))_(6)]`
`(i) [Cu(CN)_(4)]`

Answer

5

Explanation

`[PtCl_(6)]^(2-)," "[Ni(NH_(3))_(4)]^(2+)`,
`[Fe(C_(2)O_(4))]^(3-), " " [Co(en)_(3)]^(3+)`,
`[Fe(CN)_(6)]^(3-) or [Fe(CN)_(6)]^(4-)`,
`[PtCl_(4)]^(2-), " " [Ni(CO)_(4)]`,
`[Cu(CN)_(4)]^(3-), " " [Co(NH_(3))_(6)]^(2+)`