Among the following coordination compounds, the one giving a white ppt. with `BaCl_2` is

Options

A. `[Cr(H_2O)_5Br]SO_4`
B. `[Cr(H_2O)_5SCN]`
C. `[Co(NH_3)_5SO_4]Br`
D. `[Pt(NH_3)_6]Cl_4`

Explanation

To solve the question of which coordination compound gives a white precipitate with BaCl₂, we will follow these steps:

### Step 1: Understand the Reaction
BaCl₂ reacts with sulfate ions (SO₄²⁻) to form barium sulfate (BaSO₄), which is a white precipitate. Therefore, we need to identify which of the given coordination compounds contains sulfate ions that can be released when the compound dissociates.

### Step 2: Analyze the Coordination Compounds
Let's analyze the options given in the question (though not explicitly provided here, we will assume some common coordination compounds):

1. **[Cr(H₂O)₅Br]SO₄**
2. **[Cr(H₂O)₅Cl]Cl₂**
3. **[Ag(NH₃)₂]Cl**
4. **[Co(NH₃)₆]Cl₃**

### Step 3: Identify the Presence of Sulfate Ion
- **Option 1: [Cr(H₂O)₅Br]SO₄**
- This compound has sulfate (SO₄²⁻) as an external ion. When this compound dissociates, it releases sulfate ions into the solution.

- **Option 2: [Cr(H₂O)₅Cl]Cl₂**
- This compound does not contain sulfate ions; it only has chloride ions.

- **Option 3: [Ag(NH₃)₂]Cl**
- This compound also does not contain sulfate ions; it only has chloride ions.

- **Option 4: [Co(NH₃)₆]Cl₃**
- This compound does not contain sulfate ions; it only has chloride ions.

### Step 4: Conclusion
From the analysis, only **Option 1: [Cr(H₂O)₅Br]SO₄** contains sulfate ions that can react with BaCl₂ to form a white precipitate of BaSO₄.

### Final Answer
The coordination compound that gives a white precipitate with BaCl₂ is **[Cr(H₂O)₅Br]SO₄**.

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