The oxidation state of metal in metal carbonyl is

Options

A. 0
B. 1
C. 2
D. 3

Answer

To determine the oxidation state of the metal in metal carbonyl complexes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Nature of Carbonyl Ligands**:
- Carbonyl (CO) is a neutral ligand, meaning it does not carry any charge when it coordinates with the metal.

2. **Identify the Metal's Interaction with Carbonyl**:
- In metal carbonyl complexes, the metal atom forms bonds with the carbonyl ligands. The bonding involves the donation of electron density from the carbonyl to the metal's vacant d-orbitals.

3. **Determine the Charge Contribution**:
- Since carbonyl is a neutral ligand, it does not contribute any positive or negative charge to the overall charge of the complex.

4. **Calculate the Oxidation State of the Metal**:
- The oxidation state of the metal can be determined using the formula:
\[ \text{Oxidation State of Metal} + \text{Sum of Charges of Ligands} = \text{Overall Charge of Complex} \]
- In the case of metal carbonyls, the overall charge of the complex is zero (as they are typically neutral). Therefore, we can express this as:
\[ \text{Oxidation State of Metal} + 0 = 0 \]
- This implies that the oxidation state of the metal is zero.

5. **Conclusion**:
- Thus, the oxidation state of the metal in metal carbonyl complexes is 0.

### Final Answer:
The oxidation state of the metal in metal carbonyl is **0**.

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