Solid `Ba(NO_(3))` is gradually dissolved in a `1.0xx10^(-4) M Na_(2)CO_(3)` solution. At what concentrations of `Ba^(2+)`, will a precipitate begin to form?
(`K_(SP)` for `BaCO_(3)=5.1xx10^(-9)`)
A. `4.1 xx 10^(-5)M`
B. `5.1 xx 10^(-5)M`
C. `8.1 xx 10^(-8)M`
D. `8.1 xx 10^(-7)M`