Halogénu

Halogénu refers to a group of five non-metallic chemical elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). These elements are found in Group 17 of the periodic table. The name "halogen" comes from Greek words meaning "salt-former," reflecting their tendency to react with metals to form salts.

In their elemental state, halogens exist as diatomic molecules. They are highly reactive and are strong oxidizing agents. Fluorine is the most electronegative and reactive element, while reactivity decreases down the group. Halogens gain one electron to achieve a stable electron configuration, forming halide ions with a charge of -1.

Halogens exhibit a range of physical properties. Fluorine and chlorine are gases at room temperature, bromine is a liquid, and iodine and astatine are solids. Their colors vary from pale yellow for fluorine to dark violet for iodine.

These elements and their compounds have numerous applications. Chlorine is used in water purification and the production of plastics. Fluorine is found in toothpaste and refrigerants. Bromine compounds are used as flame retardants. Iodine is essential for thyroid function and is used as an antiseptic. Astatine, being radioactive and rare, has limited practical use, though it is studied for potential medical applications.