How many element are present in the third period of the p-block elements ?

Explanation

To determine how many elements are present in the third period of the p-block elements, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Third Period Elements**: The third period of the periodic table includes the elements from sodium (Na) to argon (Ar). The elements in this period are:
- Sodium (Na)
- Magnesium (Mg)
- Aluminum (Al)
...