Oxidation state of Ni in `Ni(CO)_4` is

Options

A. `+2`
B. `0`
C. `+4`
D. `-8`

Explanation

To determine the oxidation state of nickel (Ni) in the complex compound \( Ni(CO)_4 \), we can follow these steps:

### Step 1: Identify the components of the compound
The compound \( Ni(CO)_4 \) consists of one nickel atom and four carbon monoxide (CO) ligands.

### Step 2: Assign oxidation states to the ligands
In coordination compounds, the oxidation state of neutral ligands is typically zero. The carbon monoxide (CO) ligand is a neutral ligand, meaning it does not contribute any charge. Therefore, the oxidation state of each CO is 0.

### Step 3: Set up the equation for the oxidation state
Let the oxidation state of nickel be represented by \( x \). Since there are four CO ligands, the total contribution from the ligands to the oxidation state is \( 4 \times 0 = 0 \).

### Step 4: Write the equation
The overall charge of the complex \( Ni(CO)_4 \) is neutral (0). Therefore, we can write the equation:
\[ x + 0 = 0 \]

### Step 5: Solve for the oxidation state of nickel
From the equation, we have:
\[ x = 0 \]

### Conclusion
The oxidation state of nickel in \( Ni(CO)_4 \) is 0.

### Final Answer
The oxidation state of Ni in \( Ni(CO)_4 \) is 0.

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