Which of the following is NOT an example of how the general solubility rules apply?

• A. BaSO4 does not dissolve well in water because most barium sulfates are insoluble.
• B. NaCl dissolves readily in water because most sodium salts are soluble.
• C. AgCl remains largely undissolved in water because most silver halides are insoluble.
• D. KNO3 is insoluble in water because most potassium salts do not dissolve.

Answer: (D)

Verified step by step guidance

1. Review the general solubility rules, which state that most alkali metal salts (such as potassium salts) and nitrates are soluble in water.
2. Analyze each statement by comparing it to these rules: BaSO4 is generally insoluble, so it fits the rule; NaCl is soluble, fitting the rule; AgCl is mostly insoluble, fitting the rule.
3. Focus on the statement about KNO3, which claims it is insoluble because most potassium salts do not dissolve. This contradicts the solubility rules since potassium salts are typically soluble.
4. Conclude that the statement about KNO3 is incorrect because it does not align with the general solubility rules.
5. Therefore, identify the KNO3 statement as the one that is NOT an example of how the general solubility rules apply.