In the periodic table, going down in fluorine group

Options

A. reactivity will increase
B. electronegativity will increase
C. ionic radius will increase
D. ionisation potential will increase

Answer

**Step-by-Step Solution:**

1. **Identify the Group in the Periodic Table:**
- The question refers to the fluorine group, which is also known as the halogen group (Group 17) in the periodic table. The elements in this group include fluorine (F), chlorine (Cl), bromine (Br), and iodine (I).

2. **Analyze Reactivity:**
- Reactivity of nonmetals generally decreases as you move down the group. For halogens, this means that fluorine is the most reactive, followed by chlorine, bromine, and iodine.
- This trend occurs because reactivity in nonmetals is directly related to their electronegativity. The higher the electronegativity, the more reactive the nonmetal.

3. **Understand Electronegativity Trend:**
- Electronegativity decreases from fluorine to iodine. Fluorine has the highest electronegativity, while iodine has the lowest in this group. Therefore, as you go down the group from fluorine to iodine, the reactivity decreases.

4. **Examine Ionic Radius:**
- The ionic radius increases as you move down the group. This is due to the addition of extra principal energy levels (shells) as you go from fluorine to iodine.
- For example:
- Fluorine (2 shells)
- Chlorine (3 shells)
- Bromine (4 shells)
- Iodine (5 shells)
- As the number of shells increases, the size of the ions increases.

5. **Consider Ionization Potential:**
- Ionization potential (or ionization energy) generally decreases as you move down a group. This is because the atomic size increases, making it easier to remove an electron from the outer shell.
- Therefore, the ionization potential is inversely proportional to atomic size.

6. **Conclusion:**
- In summary, as you go down the fluorine group:
- Reactivity decreases (due to decreasing electronegativity).
- Ionic radius increases (due to the addition of shells).
- Ionization potential decreases (due to increasing atomic size).