Which group of elements are kept in the given table? What happens to the reactivity of the elements when moving top to bottom? Why? F Cl Br I

The given table represents the Group 17 (Halogens) of the periodic table.

Reactivity Trend:

When moving top to bottom in Group 17, the reactivity of the elements decreases. This happens due to the following reasons:

1. Increase in Atomic Size: As we move down the group, the atomic size increases because new electron shells are added. This makes it harder for the nucleus to attract incoming electrons (e.g., during bonding).
2. Decrease in Electronegativity: The ability to attract electrons decreases because the outermost electrons are farther from the nucleus and experience weaker nuclear attraction.
3. Weakening Bond Formation: Larger atoms form weaker bonds with other elements, reducing their reactivity.

Thus, fluorine (F) is the most reactive halogen, while iodine (I) is the least reactive among the listed elements.