Question

At `20^(@)C`, the `Ag^(+)` ion concentration in a saturated solution `Ag_(2)CrO_(4)` is `1.5 x10^(-4)` mol `//` litre. At `20^(@)C`, the solubility product of `Ag_(2)CrO_(4)` would be
A. `3.3750 xx 10^(-12)`
B. `1.6875 xx 10^(-10)`
C. `1.6875 xx 10^(-12)`
D. `1.6875 xx 10^(-11)`

Answer 1

Correct Answer - C
`Ag_(2)CrO_(4) hArr 2Ag^(+)+CrO_(4)^(-2)`
Given `[2Ag^(+)]=1.5 xx 10^(-4) mol L^(-1)`
Thus, `[Ag^(+)]=0.75xx 10^(-4) mol L^(-1)`
Thus `[CrO_(4)^(-2)]=0.75 xx 10^(-4) mol L^(-1)`
`K_(sp)=[Ag^(+)]^(2) [CrO_(4)^(-2)]^(2)`
`=(1.5 xx 10^(-4))^(2)(0.75 xx 10^(-4))`
`=1.6875xx 10^(-12)mol^(3)L^(-3)`