A solution is 0.10 M AgNO3 and 0.10 M Ba(NO3)2. If solid Na2SO4 is added to the solution, what is [Ba2+] when Ag2SO4 begins to precipitate? (Ksp BaSO4 = 1.1 x 10-10; Ag2SO4 = 1.1 x 10-5)
1. 2.4 x 10-6 M
2. 1.0 x 10-7 M
3. 2.4 x 10-7 M
4. 3.2 x 10-6 M
5. 5.1 x 10-6 M