Comment on the reactivity of group 17 elements.

Explanation

### Step-by-Step Solution:

1. **Identify Group 17 Elements**:
Group 17 elements are known as halogens. This group includes Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At).

2. **Reactivity of Halogens**:
Halogens are known to be the most reactive nonmetals in the periodic table. Their high reactivity is due to their strong tendency to gain one electron to achieve a stable electron configuration (octet).

...