If `Ag^(+)+NH_(3)hArr[Ag(NH_(3))]^(+)`, `K_(1)=3.5xx10^(-3)` and `[Ag(NH_(3))]^(+)+NH_(3)hArr[Ag(NH_(3))_(2)]^(+)`, `K_(2)=1.74xx10^(-3)`. The formation constant of `[Ag(NH_(3))_(2)]^(+)` is :

Options

A. `6.08xx10^(-6)`
B. `6.8xx10^(-6)`
C. `1.6xx10^(3)`
D. `1.088xx10^(7)`

Explanation

`K_(1)=([Ag(NH_(3))]^(+))/([Ag^(+)][NH_(3)])=3.5xx10^(-3)`...(`i`)
`K_(2)=([Ag(NH_(3))_(2)]^(+))/([Ag(NH_(3))]^(+)[NH_(3)])=1.74xx10^(-3)`....(`ii`)
`K_(3)=K_(1)xxK_(2)=([Ag(NH_(3))_(2)]^(+))/([Ag^(+)][NH_(3)]^(2))` ....(`iii`)
`K_(3)` for `Ag^(+)+2NH_(3)to[Ag(NH_(3))_(2)]^(+)`
By eqs. (`i`), (`ii`) and (`iii`),
`K_(3)=K_(1)xxK_(2)`
`=3.5xx10^(-3)xx1.74xx10^(-3)`
`=6.08xx10^(-6)`