The correct of the metallic character is `:`

Options

A. `Na gt Mg gt Al gt Si`
B. `Mg gt Na gt Al gt Si`
C. `Al gt Mg gt Na gt Si`
D. `Si gt Al gt Na gt Mg`

Explanation

To determine the correct order of metallic character among the elements sodium (Na), magnesium (Mg), aluminium (Al), and silicon (Si), we need to consider the periodic trends in metallic character.

### Step-by-Step Solution:

1. **Understanding Metallic Character**:
- Metallic character refers to the ability of an element to lose electrons and form positive ions (cations). Metals tend to lose electrons easily, while non-metals tend to gain electrons.

2. **Periodic Trends**:
- As we move from left to right across a period in the periodic table, the metallic character decreases. This is due to the increase in nuclear charge, which pulls the electrons closer to the nucleus, making it harder for the atom to lose electrons.

3. **Analyzing the Elements**:
- The elements given are sodium (Na), magnesium (Mg), aluminium (Al), and silicon (Si).
- Sodium (Na) is located in Group 1, magnesium (Mg) in Group 2, aluminium (Al) in Group 13, and silicon (Si) in Group 14.

4. **Size and Nuclear Attraction**:
- Sodium has the largest atomic size among these elements, which means it has the weakest nuclear attraction for its outermost electron. Therefore, it can lose its outermost electron most easily.
- Magnesium is smaller than sodium but larger than aluminium and silicon, so it can still lose electrons but not as easily as sodium.
- Aluminium is smaller than magnesium, making it harder to lose electrons compared to sodium and magnesium.
- Silicon, being the smallest in size among these four, has the strongest nuclear attraction and thus the least metallic character.

5. **Ordering the Elements**:
- Based on the above analysis, the order of metallic character from highest to lowest is:
- Sodium (Na) > Magnesium (Mg) > Aluminium (Al) > Silicon (Si)

6. **Conclusion**:
- Therefore, the correct order of metallic character is: **Sodium (Na), Magnesium (Mg), Aluminium (Al), Silicon (Si)**.

### Final Answer:
The correct order of metallic character is: **Sodium (Na) > Magnesium (Mg) > Aluminium (Al) > Silicon (Si)**.