According to common solubility rules, which of the following compounds is generally insoluble in water?

• A. NaNO_3
• B. K_2SO_4
• C. NH_4Br
• D. AgCl

Answer: (D)

Verified step by step guidance

1. Recall the common solubility rules for ionic compounds in water, which help predict whether a compound will dissolve or remain insoluble.
2. Identify that compounds containing alkali metal ions (such as Na⁺ and K⁺) and the ammonium ion (NH₄⁺) are generally soluble in water.
3. Recognize that nitrates (NO₃⁻), sulfates (SO₄²⁻), and bromides (Br⁻) are typically soluble, except for some exceptions not involving the given compounds.
4. Note that silver chloride (AgCl) is a classic example of an insoluble salt because silver halides (AgX, where X = Cl, Br, I) have low solubility in water.
5. Conclude that among the listed compounds, AgCl is generally insoluble in water according to the solubility rules.