Question

silver ions are added to a solution with Br- = Cl- = (Co3)2- = (AsO4)3- = 0.1M which compound will precipitate with lowest Ag+

Answer 1

See for the ions to precipitate ionic product should exceed ksp. So the correct answer is AgBr because it has lowest value of moles of ag among others and even its ionic product is more than ksp

Answer 2

Answer:

Ag3AsO4

Explanation:

Precipitation occurs when the ionic product of the solute exceeds the solubility product Ksp.

Thus, ionic product is the product of the concentration of the ions Qsp = [M+][A-]

For precipitation - Ksp<Qsp

Thus, the lesser the solubility of the product, the lesser the concentration of the ions is required.

Since the concentration of anion is same, the concentration of Ag+ will be required the least in case that has the lowest solubility product which will be Ag3AsO4 with Ksp = 10 -22.