Based on solubility rules, which of the following ions generally form insoluble compounds with Ag^+ in water?

• A. Na^+
• B. NO_3^-
• C. SO_4^{2-}
• D. Cl^-

Answer: (D)

Verified step by step guidance

1. Recall the common solubility rules for ionic compounds in water, focusing on silver ion (Ag^+).
2. Identify that most compounds containing Na^+ (sodium ion) and NO_3^- (nitrate ion) are generally soluble in water.
3. Note that SO_4^{2-} (sulfate ion) compounds are mostly soluble, with some exceptions like BaSO_4 and PbSO_4, but not typically insoluble with Ag^+.
4. Recognize that Ag^+ forms insoluble compounds with halide ions such as Cl^-, Br^-, and I^-, due to the low solubility of silver halides.
5. Conclude that among the given ions, Cl^- is the one that generally forms insoluble compounds with Ag^+ in water.