Which of the following metals exhibits more than one oxidation state ?

Options

A. Na
B. Mg
C. Fe
D. Al

Answer

To determine which of the given metals exhibits more than one oxidation state, we can analyze the electronic configurations and oxidation states of the metals listed.

### Step-by-Step Solution:

1. **Identify the Metals**: First, we need to know which metals are being considered in the question. Common examples include sodium (Na), magnesium (Mg), aluminum (Al), and iron (Fe).

2. **Determine the Atomic Numbers and Electronic Configurations**:
- Sodium (Na): Atomic number = 11
- Electronic configuration: 1s² 2s² 2p⁶ 3s¹
- Magnesium (Mg): Atomic number = 12
- Electronic configuration: 1s² 2s² 2p⁶ 3s²
- Aluminum (Al): Atomic number = 13
- Electronic configuration: 1s² 2s² 2p⁶ 3s² 3p¹
- Iron (Fe): Atomic number = 26
- Electronic configuration: [Ar] 4s² 3d⁶

3. **Analyze Oxidation States**:
- Sodium typically exhibits an oxidation state of +1 (losing one electron).
- Magnesium typically exhibits an oxidation state of +2 (losing two electrons).
- Aluminum can exhibit oxidation states of +1 and +3 (losing three electrons).
- Iron can exhibit multiple oxidation states, commonly +2 and +3, due to the involvement of both 4s and 3d electrons.

4. **Conclusion**:
- Among the metals listed, iron (Fe) is the only metal that exhibits more than one oxidation state (+2 and +3). Sodium, magnesium, and aluminum have limited oxidation states.

### Final Answer:
Iron (Fe) exhibits more than one oxidation state.