B⁻, or the boron anion, is a negatively charged ion formed when a boron atom gains an extra electron. Boron, represented by the symbol B, is a chemical element with atomic number 5. In its anionic form, B⁻ can participate in various chemical reactions, often acting as a reducing agent. This anion is significant in the field of chemistry, particularly in the study of boron compounds and their applications. B⁻ can be involved in the formation of boranes, which are compounds containing boron and hydrogen, and are used in organic synthesis and materials science.