Pb(NO3)2 is soluble. Pb2+ will form precipitate PbCl2 with Cl-. [Cl-] decreases, shifting AgCl equilbirum to the right. So addition of Pb(NO3)2 has increased AgCl solubility.
No. Concentration of Cl
- in saturated AgCl solution is way too low for PbCl
2 precipitation. It may work other way around - adding AgNO
3 to PbCl
2 solution. But I am not sure I will decide to call this situation "increased solubility". Depends how you define solubility - note that you don't have more PbCl
2 in the solution, just more Pb
2+. That's not the same thing.
studytogether: adding an inert salt increases ionic strength of the solution, lowering ions activities. This will increase solubility for sure.