The oxidation state of Ni in `[Ni(CO)_4]` is

Options

A. 0
B. 2
C. 3
D. 4

Explanation

To determine the oxidation state of nickel (Ni) in the complex `[Ni(CO)4]`, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the overall charge of the complex**:
The complex `[Ni(CO)4]` is neutral, meaning its overall charge is 0.

2. **Determine the contribution of the ligands**:
In this complex, the ligand is carbon monoxide (CO). CO is a neutral ligand, which means it does not contribute any charge. Therefore, the total contribution from the four CO ligands is:
\[ 4 \times 0 = 0 \]

3. **Set up the equation for oxidation state**:
Let the oxidation state of nickel be represented as \( x \). Since the total charge of the complex is 0, we can write the equation:
\[ x + (4 \times 0) = 0 \]

4. **Solve for \( x \)**:
Simplifying the equation gives:
\[ x = 0 \]

5. **Conclusion**:
The oxidation state of nickel in the complex `[Ni(CO)4]` is 0.

### Final Answer:
The oxidation state of Ni in `[Ni(CO)4]` is **0**.

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