The correct order of the size of `Be`, `C`, `F` and `Ne` is

Options

A. `Be gt C gt F gt Ne`
B. `Be lt C lt F lt Ne`
C. `F lt C lt S lt P`
D. `Be gt C gt F lt Ne`

Explanation

To determine the correct order of the size of the elements Beryllium (Be), Carbon (C), Fluorine (F), and Neon (Ne), we need to understand how atomic size varies across a period in the periodic table.

### Step-by-Step Solution:

1. **Identify the Elements and Their Positions**:
- Beryllium (Be) is in Group 2 and Period 2.
- Carbon (C) is in Group 14 and Period 2.
- Fluorine (F) is in Group 17 and Period 2.
- Neon (Ne) is in Group 18 and Period 2.

2. **Understand Atomic Size Trends**:
- Atomic size decreases as you move from left to right across a period. This is due to the increase in nuclear charge (more protons) which pulls the electrons closer to the nucleus, reducing the atomic radius.
- In Period 2, the order of atomic size from largest to smallest is: Li > Be > B > C > N > O > F > Ne.

3. **Compare the Elements**:
- Among the elements Be, C, F, and Ne:
- Beryllium (Be) is the largest because it is the furthest left in the period.
- Carbon (C) is smaller than Beryllium.
- Fluorine (F) is smaller than Carbon.
- Neon (Ne) is the smallest since it is an inert gas and has a complete outer shell, which results in a smaller atomic radius compared to the other elements in the same period.

4. **Establish the Order**:
- Based on the above comparisons, the order of size from largest to smallest is:
- Be > C > F > Ne.

5. **Final Answer**:
- Therefore, the correct order of the size of Be, C, F, and Ne is:
- Beryllium (Be) > Carbon (C) > Fluorine (F) > Neon (Ne).