`10^(-4)` mol `Pb(NO_3)_2,10^(-4)` mol `Ca(NO_3)_2` and `10^(-3)` mol `Na_2CO_3` are added to 500 mL of water. Will there be any precipitation? If so, which will be precipitated? [Given: `K_(sp)(PbCO_3)=7.4xx10^(-14)` and `K_(sp)(CaCO_3)=6.0xx10^(-9)`]

Explanation

In the solution, `[Pb^(2+)]=10^(-4)xx(1000)/(500)=2xx10^(-4)(M)`
`[Ca^(2+)]=10^(-4)xx(1000)/(500)=2xx10^(-4)(M)`
`[CO_3^(2-)]=10^(-3)xx(1000)/(500)=2xx10^(-3)(M)`
`PbCO_3(s) `[Pb^(2+)][CO_3^(2-)]=2xx10^(-4)xx2xx10^(-3)=4xx10^(-7)`
`>K_(sp)(CaCO_3)`
`CaCO_3(s) `[Ca^(2+)][CO_3^(2-)]=2xx10^(-4)xx2xx10^(-3)`
`=4xx10^(-7)>K_(sp)(CaCO_3)`
So, both `PbCO_3` and `CaCO_3` will get precipitated.