Match the atomic number 2, 4, 8, 15 and 19 with the following:
A solid non-metal belonging to the third period.

Explanation

To solve the problem of matching the atomic numbers 2, 4, 8, 15, and 19 with the description of "a solid non-metal belonging to the third period," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Periods and Groups in the Periodic Table**:
- The periodic table is organized into periods (horizontal rows) and groups (vertical columns). The third period consists of elements with atomic numbers from 11 to 18.

2. **List the Elements in the Third Period**:
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