Arsenous sulphide sol is prepared by passing `H_(2)S ` through arsenous oxide solution . The charge developed on the particles is due to adsorption of :

Options

A. `H^(+)`
B. `S^(2-)`
C. `OH^(-)`
D. `O^(2-)`

Answer

To solve the question regarding the charge developed on the particles in arsenous sulfide sol, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- Arsenous sulfide (As₂S₃) is prepared by passing hydrogen sulfide (H₂S) through a solution of arsenous oxide (As₂O₃). This indicates that we are forming a colloidal solution of arsenous sulfide.

2. **Identifying the Components**:
- In the reaction, we have arsenous oxide (As₂O₃) and hydrogen sulfide (H₂S). When H₂S is introduced to the arsenous oxide solution, it reacts to form arsenous sulfide.

3. **Formation of Colloidal Solution**:
- The reaction can be summarized as:
\[ \text{As}_2\text{O}_3 + 3 \text{H}_2\text{S} \rightarrow \text{As}_2\text{S}_3 + 3 \text{H}_2\text{O} \]
- This results in the formation of a colloidal solution of arsenous sulfide (As₂S₃).

4. **Charge Development**:
- The particles in the colloidal solution acquire a charge due to the adsorption of ions from the surrounding solution. In this case, the ions of interest are those from the H₂S solution.

5. **Identifying the Adsorbed Ion**:
- The possible ions that could be adsorbed are:
- H⁺ (hydrogen ion)
- S²⁻ (sulfide ion)
- O²⁻ (oxide ion)
- OH⁻ (hydroxide ion)
- Since H₂S dissociates to provide S²⁻ ions in solution, these ions are likely to be adsorbed onto the surface of the colloidal particles.

6. **Conclusion**:
- The charge developed on the arsenous sulfide particles is primarily due to the adsorption of S²⁻ ions from the H₂S solution. Therefore, the correct answer is **S²⁻ ions**.

### Final Answer:
The charge developed on the particles is due to the adsorption of **S²⁻ ions**.

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