Which metal represents more than one oxidation state

Options

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

Explanation

To determine which metal represents more than one oxidation state, we can analyze the oxidation states of various metals, particularly focusing on transition metals and their characteristics.

### Step-by-Step Solution:

1. **Understanding Oxidation States**:
- Oxidation state refers to the degree of oxidation of an atom in a compound. It can vary based on the number of electrons lost or gained.

2. **Identifying Transition Metals**:
- Transition metals are found in the d-block of the periodic table. They are known for having variable oxidation states due to their ability to lose different numbers of electrons from their d and s orbitals.

3. **Examples of Transition Metals**:
- Common transition metals include iron (Fe), copper (Cu), and manganese (Mn). Each of these metals can exhibit multiple oxidation states.
- For example:
- Iron can exist in +2 (ferrous) and +3 (ferric) oxidation states.
- Copper can exist in +1 (cuprous) and +2 (cupric) oxidation states.
- Manganese can have oxidation states ranging from +2 to +7.

4. **Analyzing Other Metals**:
- Non-transition metals, such as aluminum (Al) and sodium (Na), typically exhibit only one oxidation state. Aluminum primarily shows +3 oxidation state, while sodium shows +1 oxidation state.
- Therefore, they do not represent more than one oxidation state.

5. **Conclusion**:
- The metals that represent more than one oxidation state are primarily transition metals due to their partially filled d orbitals, which allow for variable electron loss.

### Final Answer:
Transition metals represent more than one oxidation state, such as iron (Fe), copper (Cu), and manganese (Mn).