Answer: the group 7 includes fluorine (atomic symbol F), chlorine (atomic symbol Cl), bromine (atomic symbol Br), iodine (atomic symbol I), and astatine (atomic symbol At)
Explanation: Their reactivity decreases down the group. Halogens show different physical properties based on their positions in the periodic table. Physical properties include conductivity, electronegativity, melting and boiling points. All halogens are non-metals and are diatomic in the gaseous state. The non-metallic character decreases from fluorine to iodine