Which other elements are in the halogen group with chlorine?

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A labeled diagram of the chlorine element from the periodic table shows its atomic number 17, symbol Cl, electron configuration, and atomic weight range. The box is shaded green to indicate chlorine is a halogen, with icons for orthorhombic crystal structure, gas state at room temperature, and strong acidity. A key explains the icons and colors used. — chlorine Properties of chlorine.

The halogen group, designated as Group 17 of the periodic table, consists of six nonmetallic elements. In addition to chlorine, the group includes the following elements:

Fluorine (F)
Bromine (Br)
Iodine (I)
Astatine (At)
Tennessine (Ts)

These elements are characterized by having seven valence electrons in their outermost electron shell, which contributes to their high reactivity and their tendency to act as strong oxidizers.123