What type of ions have a negative charge?

Anions are ions that carry a negative charge. This occurs when an atom gains one or more electrons, resulting in an excess of negatively charged particles compared to positively charged protons. Because the number of protons remains constant, the added electrons lead to a net negative charge for the ion.

In contrast, cations are positively charged ions formed when an atom loses electrons, leading to more protons than electrons. Neutrons are neutral particles found in the nucleus of an atom and do not carry any charge. Radicals are atoms or molecules with unpaired electrons, which may have different overall charges but are not specifically categorized as negative ions. Thus, anions are distinctly identified by their negative charge.