Which is/are insoluble in `NH_(3)` solution?

Options

A. AgCl
B. AgBr
C. AgI
D. `Ag_(2)S`

Answer

To determine which compounds are insoluble in ammonia (NH₃) solution, we will analyze the solubility of the given silver halides and sulfide in ammonia.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds we are considering are:
- Silver Chloride (AgCl)
- Silver Bromide (AgBr)
- Silver Iodide (AgI)
- Silver Sulfide (Ag₂S)

2. **Understand Solubility in Ammonia**:
- Ammonia can form soluble complexes with certain silver compounds. Specifically, AgCl and AgBr can form soluble complexes with ammonia, while AgI and Ag₂S do not.

3. **Analyze Each Compound**:
- **AgCl**:
- When AgCl is treated with ammonia, it forms a soluble complex:
\[ \text{AgCl} + 2 \text{NH}_3 \rightarrow \text{[Ag(NH}_3\text{)}_2]^+ + \text{Cl}^- \]
- Therefore, AgCl is soluble in ammonia.

- **AgBr**:
- Similarly, AgBr also forms a soluble complex with ammonia:
\[ \text{AgBr} + 2 \text{NH}_3 \rightarrow \text{[Ag(NH}_3\text{)}_2]^+ + \text{Br}^- \]
- Thus, AgBr is soluble in ammonia.

- **AgI**:
- Silver iodide does not form a soluble complex with ammonia:
\[ \text{AgI} \text{ remains insoluble in NH}_3 \]
- Therefore, AgI is insoluble in ammonia.

- **Ag₂S**:
- Silver sulfide also does not form a soluble complex with ammonia:
\[ \text{Ag}_2\text{S} \text{ remains insoluble in NH}_3 \]
- Thus, Ag₂S is also insoluble in ammonia.

4. **Conclusion**:
- The compounds that are insoluble in ammonia solution are:
- Silver Iodide (AgI)
- Silver Sulfide (Ag₂S)

### Final Answer:
The compounds that are insoluble in NH₃ solution are AgI (Silver Iodide) and Ag₂S (Silver Sulfide).