Explain the difference between an anion and a cation.

Anions and cations are both types of ions, which are atoms or molecules that have gained or lost electrons and thus have a net charge.

Anion

• Definition: An anion is a negatively charged ion.
• Formation: Anions are formed when an atom or molecule gains one or more electrons.
• Example: Common anions include chloride (Cl⁻), sulfate (SO₄²⁻), and nitrate (NO₃⁻).

Cation

• Definition: A cation is a positively charged ion.
• Formation: Cations are formed when an atom or molecule loses one or more electrons.
• Example: Common cations include sodium (Na⁺), calcium (Ca²⁺), and ammonium (NH₄⁺).

Key Differences

• Charge: Anions have a negative charge, while cations have a positive charge.
• Electron Movement: Anions gain electrons, whereas cations lose electrons.
• Role in Compounds: In ionic compounds, anions and cations attract each other to form stable structures, such as in table salt (NaCl), where Na⁺ is the cation and Cl⁻ is the anion.

These differences are fundamental in understanding chemical reactions and the formation of compounds.