Let the solubilities of AgCl in H2O, 0.01M CaCl2, 0.01M NaCl and 0.05M AgNO3 be S1, S2, S3 and S4 respectively. What is the correct relationship between these quantities ?

When the concentration of NaCl is less than 1 M no complexation reaction occurs with Ag+; but common-ion effect will be exerted on the solubility of AgCl.In 0.05 M AgNO3, the solubility of AgCl will be least as the [Ag+] is higher than the concentration of [Cl-] in all other cases.