Which description matches an anion?

• A. Positive ion.
• B. Neutral particle.
• C. Electron.
• D. Negative ion.

Answer: (D)

An anion is a negatively charged ion, formed when an atom or molecule gains one or more electrons, giving it a net negative charge. That description fits because the defining feature of anions is their extra electrons and resulting negative charge. A positive ion, by contrast, is called a cation and has lost electrons, giving it a positive charge. A neutral particle has no net charge, meaning it has the same number of protons and electrons. An electron is a negatively charged particle, but by itself it’s not an ion; ions are atoms or molecules with a net charge, which can arise from gaining or losing electrons.