* Fluorine (F)
* Chlorine (Cl)
* Bromine (Br)
* Iodine (I)
* Astatine (At)
* Tennessine (Ts)
Key characteristics of halogens:
* Highly reactive nonmetals: They readily form compounds with other elements, especially metals.
* Exist as diatomic molecules: They are found in nature as pairs of atoms (e.g., Cl₂, Br₂).
* Form salts with metals: The halogens react with metals to form ionic compounds called salts.
* Electronegative: They have a strong tendency to attract electrons.
* Varying states at room temperature: Fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid.
* Important in biological systems: Halogens play crucial roles in human health, such as chlorine in disinfectants and iodine in thyroid hormone production.
