What type of ion do elements from Group 7 typically form?

Elements from Group 7 of the periodic table, known as the halogens, typically form negative ions, specifically anions. This occurs because halogens have seven electrons in their outermost shell and require one additional electron to achieve a stable electronic configuration resembling that of noble gases. By gaining an electron, they become negatively charged ions, known as halide ions. For example, chlorine can gain an electron to form the chloride ion (Cl⁻).

This tendency to gain an electron and form negative ions is a defining characteristic of halogens. It explains their behavior in chemical reactions, particularly with metals, which typically lose electrons to form positive ions. Thus, the formation of negative ions is what sets Group 7 elements apart in terms of their reactivity and bonding properties.