According to general solubility rules, which type of anion will typically result in an insoluble compound when combined with most cations?

• A. NO_3^- (nitrate)
• B. SO_4^{2-} (sulfate)
• C. Cl^- (chloride)
• D. CO_3^{2-} (carbonate)

Answer: (D)

Verified step by step guidance

1. Recall the general solubility rules which help predict whether an ionic compound will dissolve in water or form a precipitate (insoluble compound).
2. Identify common anions that usually form soluble compounds with most cations, such as nitrate (\(NO_3^-\)), sulfate (\(SO_4^{2-}\)), and chloride (\(Cl^-\)). These are generally soluble except for some exceptions.
3. Recognize that carbonate (\(CO_3^{2-}\)) is an anion that typically forms insoluble compounds with most cations, except when paired with alkali metals (like \(Na^+\), \(K^+\)) or ammonium (\(NH_4^+\)).
4. Understand that the insolubility of carbonate salts arises because \(CO_3^{2-}\) tends to form strong ionic lattices that do not easily dissociate in water.
5. Conclude that among the given options, \(CO_3^{2-}\) (carbonate) is the anion that typically results in insoluble compounds with most cations according to general solubility rules.