Write the Lewis dot symbols of the following elements :
Be, Na, B, O, N, Br.

Explanation

To write the Lewis dot symbols for the elements Beryllium (Be), Sodium (Na), Boron (B), Oxygen (O), Nitrogen (N), and Bromine (Br), we need to determine the number of valence electrons for each element. The Lewis dot symbol represents the valence electrons as dots around the element's symbol.

### Step-by-Step Solution:

1. **Beryllium (Be)**:
- Atomic number: 4
- Electron configuration: 1s² 2s²
- Valence electrons: 2 (from the 2s orbital)
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