Which of the following is vaska's compound

Options

A. `[Ni(P Ph_(3))_(2)Cl_(2)]`
B. `[Rh(CO)_(2)Cl]_(2)`
C. trans-`IrCl(CO) (P Ph_(3))_(2)`
D. `IrCl(CO)_(2)(P Ph_(3))_(2)`

Explanation

To determine which of the given compounds is Vaska's compound, we first need to understand what Vaska's compound is.

### Step-by-Step Solution:

1. **Definition of Vaska's Compound**: Vaska's compound is a type of coordination complex that typically has the general formula [M(CO)Cl(PPh₃)₂], where M is a metal, CO is carbon monoxide, Cl is chloride, and PPh₃ is triphenylphosphine.

2. **Identify the Metal**: Vaska's compound is commonly associated with nickel (Ni). Therefore, we should look for a compound that contains nickel as the central metal.

3. **Check the Ligands**: The ligands in Vaska's compound include carbon monoxide (CO) and chloride (Cl), along with two triphenylphosphine (PPh₃) ligands.

4. **Structure of Vaska's Compound**: The structure of Vaska's compound is square planar. In this structure, the ligands are arranged in a way that the carbonyl and chloride ligands are trans to each other, and the two triphenylphosphine ligands are also trans to each other.

5. **Conclusion**: Based on the information provided, the compound that fits the description of Vaska's compound is the one that has nickel as the metal, carbon monoxide, chloride, and two triphenylphosphine ligands.

### Final Answer:
The Vaska's compound is **[Ni(CO)Cl(PPh₃)₂]**.

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