An element X belongs to group 17 and 2nd period of the periodic table. Its atomic number will be

Options

A. `9`
B. `14`
C. `7`
D. `15`

Explanation

To determine the atomic number of element X, which belongs to group 17 and the 2nd period of the periodic table, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Group and Period**:
- The element X is stated to belong to group 17 and the 2nd period of the periodic table.

2. **Understand the Periodic Table Layout**:
- The periodic table is organized into periods (horizontal rows) and groups (vertical columns). Group 17 is known as the halogens.

3. **Locate Group 17 in the 2nd Period**:
- In the 2nd period, the elements are:
- Lithium (Li) - Atomic number 3
- Beryllium (Be) - Atomic number 4
- Boron (B) - Atomic number 5
- Carbon (C) - Atomic number 6
- Nitrogen (N) - Atomic number 7
- Oxygen (O) - Atomic number 8
- Fluorine (F) - Atomic number 9
- Neon (Ne) - Atomic number 10

4. **Identify the Element**:
- The only element in the 2nd period that belongs to group 17 is Fluorine (F).

5. **Determine the Atomic Number**:
- The atomic number of Fluorine (F) is 9.

### Final Answer:
The atomic number of element X is **9**.

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