The compound insoluble in aqueous `NH_(3)` is

Options

A. `Agl`
B. `AgCl`
C. `ZnSO_(4)`
D. `HgCl_(2)`

Answer

To determine which compound is insoluble in aqueous NH₃, we will analyze each option provided.

### Step-by-Step Solution:

1. **Analyzing AgI (Silver Iodide)**:
- When AgI is treated with aqueous NH₃, it forms a complex: \[ \text{Ag} + \text{NH}_3 \rightarrow \text{[Ag(NH}_3\text{)}_2]^+ + \text{I}^- \]
- However, AgI is known to be insoluble in aqueous NH₃ and typically forms a yellow precipitate.
- **Conclusion**: AgI is insoluble in aqueous NH₃.

2. **Analyzing AgCl (Silver Chloride)**:
- When AgCl is treated with aqueous NH₃, it forms a soluble complex: \[ \text{AgCl} + 2\text{NH}_3 \rightarrow \text{[Ag(NH}_3\text{)}_2]^+ + \text{Cl}^- \]
- This complex is soluble in NH₃.
- **Conclusion**: AgCl is soluble in aqueous NH₃.

3. **Analyzing ZnSO₄ (Zinc Sulfate)**:
- When ZnSO₄ is treated with aqueous NH₃, it forms a complex: \[ \text{ZnSO}_4 + \text{NH}_3 \rightarrow \text{[Zn(NH}_3\text{)}_4]^{2+} + \text{SO}_4^{2-} \]
- This complex is generally soluble in NH₃.
- **Conclusion**: ZnSO₄ is soluble in aqueous NH₃.

4. **Analyzing HgCl₂ (Mercuric Chloride)**:
- When HgCl₂ is treated with aqueous NH₃, it forms a soluble complex: \[ \text{HgCl}_2 + 2\text{NH}_3 \rightarrow \text{[Hg(NH}_3\text{)}_2]Cl_2 \]
- This complex, known as mercury amidochloride, is soluble in NH₃.
- **Conclusion**: HgCl₂ is soluble in aqueous NH₃.

### Final Answer:
The compound that is insoluble in aqueous NH₃ is **AgI** (option 1).

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