According to general solubility rules, which of the following compounds is most likely to be soluble in water?

• A. BaSO_4
• B. PbSO_4
• C. NaNO_3
• D. AgCl

Answer: (C)

Verified step by step guidance

1. Recall the general solubility rules for ionic compounds in water, which help predict whether a compound will dissolve or remain mostly solid.
2. Identify that most nitrates (NO_3^-) are soluble in water without exceptions, so compounds containing the nitrate ion, such as NaNO_3, are generally soluble.
3. Recognize that sulfates (SO_4^{2-}) are usually soluble, but exceptions include BaSO_4 and PbSO_4, which are known to be poorly soluble or insoluble in water.
4. Note that most chlorides (Cl^-) are soluble, but silver chloride (AgCl) is an important exception and is considered insoluble or sparingly soluble in water.
5. Conclude that among the given compounds, NaNO_3 is the most likely to be soluble in water based on these solubility rules.