halogêneos

Halogênio (from Greek hálόs, salt, andγέν(levels), producer) is a group of elements in group 17 of the periodic table. The term "halogen" is also known as the halogens. This group consists of five nonmetals: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At), as well as the synthetic elements tennessine (Ts) and oganesson (Og).

All of the naturally occurring halogens have been known by humans for centuries. They are highly reactive nonmetals with a tendency to readily react with and form compounds with other elements. The halogens are highly electronegative, and possess a very strong tendency to attract electrons. This often results in halogen compounds such as salts and iodine crystallized in solid states presenting a salt and halogen compound resulting from halogen reacting with sodium or water.

Halogens are named from Greek words: fluorine means 'to flow,' chlorine means 'pale green,' bromine from the Greek word for the brown or purple colour, iodine is from the Greek word 'violet', and astatine from the Greek word for 'unstable'.