Which statement correctly describes Group 7 elements?

• A. They are halogens that form diatomic molecules
• B. They are noble gases that form monoatomic molecules
• C. They are alkali metals
• D. They are transition metals

Answer: (A)

Halogens are Group 7 elements, a family of nonmetals that exist in elemental form as diatomic molecules. Each halogen atom has seven valence electrons and needs one more to complete an octet, so two atoms share a pair of electrons to form a covalent bond, giving molecules like F2, Cl2, Br2, and I2. This diatomic nature is a defining feature of their elemental state. They’re highly reactive and tend to gain one electron in reactions, forming -1 ions in compounds. They are not noble gases (which are monoatomic and very inert), not alkali metals (Group 1 metals), and not transition metals (the d-block). Therefore, describing them as halogens that form diatomic molecules is the correct statement.