What is an ion?

Ions are atoms or molecules that have gained or lost electrons, giving them an electrical charge. If an atom loses electrons, it becomes a positively charged ion called a cation. Conversely, if an atom gains electrons, it becomes a negatively charged ion called an anion.

The formation of ions is important in many chemical reactions and biological processes. For instance, ionic compounds, like sodium chloride (NaCl), are formed through the electrostatic attraction between cations and anions. The charge of an ion is indicated by a superscript after the element symbol (e.g., Na+ for a sodium ion, Cl- for a chloride ion).

Ions play critical roles in maintaining cell function, transmitting nerve impulses, and regulating fluid balance in living organisms. In chemistry, ions are fundamental to understanding chemical%20bonding, solubility, and reaction mechanisms.