Which of the following complex will give white precipitate with barium chloride solution –

Options

A. `[Cr(NH_3)_5Cl]SO_4`
B. `[Cr(NH_3)_4SO_4]Cl`
C. `[Co(NH_3)_6]Br_3`
D. None of these

Answer

To determine which complex will give a white precipitate with barium chloride (BaCl₂) solution, we need to analyze the complexes provided and their potential interactions with BaCl₂.

### Step-by-Step Solution:

1. **Identify the Components of BaCl₂**:
- Barium chloride dissociates in solution to form Ba²⁺ and 2 Cl⁻ ions.

2. **Understand the Precipitation Reaction**:
- A white precipitate will form when Ba²⁺ ions react with certain anions to form insoluble salts. Common anions that can form white precipitates with Ba²⁺ include sulfate (SO₄²⁻), carbonate (CO₃²⁻), and phosphate (PO₄³⁻).

3. **Analyze the Given Complexes**:
- Let's denote the complexes as follows:
- Complex A: [CrCl₂(SO₄)]²⁻
- Complex B: [Cr(NH₃)₄Cl]⁺
- Complex C: [Cr(NH₃)₆]³⁺ + 3Br⁻

4. **Dissociate Each Complex**:
- For Complex A: It contains SO₄²⁻, which can react with Ba²⁺ to form BaSO₄ (a white precipitate).
- For Complex B: It contains Cl⁻, which does not form a precipitate with Ba²⁺ as BaCl₂ is soluble.
- For Complex C: It contains Br⁻, which also does not form a precipitate with Ba²⁺ as BaBr₂ is soluble.

5. **Conclusion**:
- Among the three complexes, only Complex A (which contains SO₄²⁻) will react with Ba²⁺ to form a white precipitate of BaSO₄.

### Final Answer:
- The complex that will give a white precipitate with barium chloride solution is **Complex A**.