What is the name of Group 17 on the periodic table?

• A. Halogens
• B. Noble gases
• C. Alkali metals
• D. Transition metals

Answer: (A)

Halogens are the elements in Group 17. They have seven electrons in their outer shell, so they are highly eager to gain one more electron to reach a stable octet. That drive to complete the outer shell makes them extremely reactive, especially with alkali metals, to form salts. In elemental form, they are nonmetals that typically exist as diatomic molecules like F2 and Cl2, and they sit in the right-hand side of the periodic table in the p-block. The name halogen comes from Greek roots meaning “salt-former,” reflecting their tendency to form salts with metals. They include fluorine, chlorine, bromine, iodine, astatine, and the heavier tennessine. This combination of high reactivity, nonmetallic character, and the seven-valence-electron configuration is why their group is called halogens.