1.Solid sodium sulfide is slowly added to 125 mL of a 0.0450 M silver nitrate solution. The concentration of sulfide ion required to just initiate precipitation is  M.

2.Solid barium acetate is slowly added to 50.0 mL of a 0.0522 M ammonium sulfite solution. The concentration of barium ion required to just initiate precipitation is  M.

3.Solid potassium hydroxide is slowly added to 150 mL of a 0.0329 M iron(III) nitrate solution. The concentration of hydroxide ion required to just initiate precipitation is  M.