Write the Lewis symbols of Mg and Al.

Answer

To write the Lewis symbols for magnesium (Mg) and aluminum (Al), we need to determine the number of valence electrons for each element based on their electron configurations.

### Step 1: Determine the Electron Configuration
- **Magnesium (Mg)**: The atomic number of magnesium is 12. Its electron configuration is:
- 1s² 2s² 2p⁶ 3s²
- This can be simplified to 2, 8, 2, indicating that magnesium has 2 electrons in its outermost shell.

- **Aluminum (Al)**: The atomic number of aluminum is 13. Its electron configuration is:
- 1s² 2s² 2p⁶ 3s² 3p¹
- This can be simplified to 2, 8, 3, indicating that aluminum has 3 electrons in its outermost shell.

### Step 2: Identify the Valence Electrons
- **Valence Electrons in Magnesium**: From the electron configuration, we see that magnesium has 2 valence electrons.
- **Valence Electrons in Aluminum**: From the electron configuration, we see that aluminum has 3 valence electrons.

### Step 3: Write the Lewis Symbols
- **Lewis Symbol for Magnesium (Mg)**: The Lewis symbol is represented by the element's symbol surrounded by dots that represent the valence electrons. For magnesium, it will have 2 dots:
- **Lewis Symbol**: Mg: ••

- **Lewis Symbol for Aluminum (Al)**: For aluminum, it will have 3 dots:
- **Lewis Symbol**: Al: •••

### Final Answer
- Lewis Symbol for Magnesium (Mg): Mg: ••
- Lewis Symbol for Aluminum (Al): Al: •••