Which one of the following elements exhibit maximum number of valence electrons?

Options

A. Na
B. AI
C. Si
D. P

Explanation

To determine which element exhibits the maximum number of valence electrons, we will analyze the electronic configurations of the given elements. Let's consider the elements mentioned in the video transcript: Sodium, Aluminum, Silicon, and Phosphorus.

### Step-by-Step Solution:

1. **Identify the Elements and Their Atomic Numbers:**
- Sodium (Na) - Atomic number 11
- Aluminum (Al) - Atomic number 13
- Silicon (Si) - Atomic number 14
- Phosphorus (P) - Atomic number 15

2. **Write the Electronic Configurations:**
- Sodium: The electronic configuration is \( 2, 8, 1 \) (which can also be written as \( 1s^2 2s^2 2p^6 3s^1 \)).
- Aluminum: The electronic configuration is \( 2, 8, 3 \) (or \( 1s^2 2s^2 2p^6 3s^2 3p^1 \)).
- Silicon: The electronic configuration is \( 2, 8, 4 \) (or \( 1s^2 2s^2 2p^6 3s^2 3p^2 \)).
- Phosphorus: The electronic configuration is \( 2, 8, 5 \) (or \( 1s^2 2s^2 2p^6 3s^2 3p^3 \)).

3. **Determine the Number of Valence Electrons:**
- Valence electrons are the electrons in the outermost shell.
- Sodium has **1** valence electron.
- Aluminum has **3** valence electrons.
- Silicon has **4** valence electrons.
- Phosphorus has **5** valence electrons.

4. **Compare the Number of Valence Electrons:**
- Sodium: 1
- Aluminum: 3
- Silicon: 4
- Phosphorus: 5

5. **Identify the Element with the Maximum Number of Valence Electrons:**
- Among the elements analyzed, Phosphorus has the highest number of valence electrons, which is **5**.

### Conclusion:
The element that exhibits the maximum number of valence electrons is **Phosphorus (P)**.