A white percipitate of AgCl dissolves in excess of
`I) NH_(3)(aq)" " II)Na_(2)S_(2)O_(3)" "III)NaCn`

Options

A. III only
B. I, II, III
C. I, II
D. I only

Answer

To solve the question regarding the solubility of a white precipitate of silver chloride (AgCl) in excess of different reagents, we will analyze each reagent one by one.

### Step-by-Step Solution:

1. **Understanding the Problem**: We have a white precipitate of silver chloride (AgCl) and we need to determine if it dissolves in excess of three different reagents:
- I) Ammonia (NH₃(aq))
- II) Sodium thiosulfate (Na₂S₂O₃)
- III) Sodium cyanide (NaCN)

2. **Reaction with Ammonia (NH₃(aq))**:
- When AgCl is treated with excess ammonia, it forms a soluble complex. The reaction can be represented as:
\[ \text{AgCl} + 2 \text{NH}_3 \rightarrow \text{[Ag(NH}_3\text{)}_2]^+ + \text{Cl}^- \]
- The complex formed is [Ag(NH₃)₂]⁺, which is soluble in water. Therefore, AgCl dissolves in excess ammonia.

**Hint**: Look for the formation of soluble complexes when silver chloride reacts with ammonia.

3. **Reaction with Sodium Thiosulfate (Na₂S₂O₃)**:
- When AgCl reacts with sodium thiosulfate, it also forms a soluble complex. The reaction can be represented as:
\[ \text{AgCl} + 2 \text{Na}_2\text{S}_2\text{O}_3 \rightarrow \text{Na}_3[\text{Ag}(\text{S}_2\text{O}_3)_2] + \text{NaCl} \]
- The complex formed is sodium argentothiosulfate, which is soluble. Thus, AgCl dissolves in excess sodium thiosulfate.

**Hint**: Identify the formation of thiosulfate complexes when silver chloride reacts with sodium thiosulfate.

4. **Reaction with Sodium Cyanide (NaCN)**:
- When AgCl is treated with sodium cyanide, it forms another soluble complex:
\[ \text{AgCl} + 2 \text{NaCN} \rightarrow \text{[Ag(CN)}_2]^- + \text{NaCl} \]
- The complex formed is [Ag(CN)₂]⁻, which is soluble in water. Therefore, AgCl dissolves in excess sodium cyanide.

**Hint**: Consider the formation of cyanide complexes when silver chloride reacts with sodium cyanide.

5. **Conclusion**:
- From the analysis above, we conclude that the white precipitate of AgCl dissolves in excess of all three reagents: ammonia (NH₃), sodium thiosulfate (Na₂S₂O₃), and sodium cyanide (NaCN).

### Final Answer:
The white precipitate of AgCl dissolves in excess of:
- I) NH₃(aq)
- II) Na₂S₂O₃
- III) NaCN

All three options are correct.