A room temperature aqueous solution is 0.10 M in zinc acetate, 0.50 M in strontium acetate and 15.2 M in nickel (II) acetate. At what concentration of carbonate does a solid first appear in the solution?
1.46 x 10-9 M
1.12 x 10-9 M
9.34 x 10-9 M
5.60 x 10-10 M