Anion -

: The number of electrons gained is indicated by a superscript after the chemical symbol (e.g., Cl−cap C l raised to the negative power for a gain of one electron, O2−cap O raised to the 2 minus power for a gain of two).

Anions are typically formed by . According to the octet rule , atoms often gain electrons until their outermost shell is full, typically containing eight electrons. This process is driven by the atom's electronegativity—its ability to attract and hold onto electrons. : The number of electrons gained is indicated

: When an atom gains an electron, it becomes an anion. : The number of electrons gained is indicated

Anions exist in various forms, from simple atoms to complex molecular groups: Cation vs Anion: Definitions & Periodic Table Guide : The number of electrons gained is indicated