An element X makes an oxide with the formula `X_2O_3`. This element will be in the same group as:

Options

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

Explanation

To determine which element belongs to the same group as element X, which forms the oxide X₂O₃, we can analyze the electronic configurations and the bonding behavior of potential candidates.

### Step-by-Step Solution:

1. **Identify the Oxide Formula**: The given oxide is X₂O₃. This indicates that element X combines with oxygen in a way that suggests it has a +3 oxidation state when forming this oxide.

2. **Determine the Valence Electrons of X**: Since the oxide is X₂O₃, element X must have 3 valence electrons. This is because two X atoms must donate a total of 6 electrons to satisfy the needs of three oxygen atoms (each needing 2 electrons).

3. **Identify Possible Elements**: Elements that typically have 3 valence electrons and form oxides with the formula X₂O₃ are found in Group 13 of the periodic table. The most common element in this group is aluminum (Al), which has the electronic configuration of 2, 8, 3.

4. **Check Other Elements**:
- **Sodium (Na)**: Sodium has 1 valence electron and forms Na₂O. It does not belong to the same group.
- **Magnesium (Mg)**: Magnesium has 2 valence electrons and forms MgO. It does not belong to the same group.
- **Aluminum (Al)**: Aluminum has 3 valence electrons and forms Al₂O₃, which matches the oxide formula X₂O₃.
- **Chlorine (Cl)**: Chlorine has 7 valence electrons and forms Cl₂O. It does not belong to the same group.

5. **Conclusion**: The only element that fits the criteria of having 3 valence electrons and forming an oxide with the formula X₂O₃ is aluminum (Al). Therefore, element X is in the same group as aluminum.

### Final Answer:
Element X is in the same group as Aluminum (Al).