Which of the following, when dissolved in yellow ammonium sulphide, forms a thiocomplex containing the metal in the oxidation state +IV?

Options

A. `As_(2)S_(3)`
B. `As_(2)S_(3)`
C. `Sb_(2)S_(3)`
D. `SnS`

Answer

To solve the question of which compound, when dissolved in yellow ammonium sulfide, forms a thiocomplex containing the metal in the oxidation state +IV, we will analyze the given compounds step by step.

### Step 1: Identify the Compounds
The compounds provided are:
1. As₂S₃ (Arsenic trisulfide)
2. As₂S₅ (Arsenic pentasulfide)
3. Sb₂S₃ (Antimony trisulfide)
4. SNS (Thiosemicarbazide)

### Step 2: Understand Yellow Ammonium Sulfide
Yellow ammonium sulfide is represented as (NH₄)₂S and is known for its ability to form thiocomplexes with certain metal sulfides.

### Step 3: Analyze Each Compound
- **As₂S₃**: When arsenic trisulfide is treated with yellow ammonium sulfide, it does not typically form a +IV oxidation state complex.
- **As₂S₅**: Similarly, arsenic pentasulfide does not form a +IV oxidation state complex with yellow ammonium sulfide.
- **Sb₂S₃**: Antimony trisulfide, when dissolved in yellow ammonium sulfide, forms a thiocomplex. The oxidation state of antimony in this thiocomplex is +IV.
- **SNS**: Thiosemicarbazide does not form a thiocomplex with yellow ammonium sulfide that contains a metal in the +IV oxidation state.

### Step 4: Conclusion
Based on the analysis, the compound that forms a thiocomplex with yellow ammonium sulfide containing the metal in the oxidation state +IV is **Sb₂S₃ (Antimony trisulfide)**.

### Final Answer
The correct option is **Sb₂S₃** (Antimony trisulfide).

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