Ions

There are several types of ions, and most are formed when atoms lose or gain electrons. The main 2 types of ions are monatomic ions and polyatomic ions. Ions are then classified by whether they have a positive charge or negative charge, leaving them classified as either a cation or anion.

Classifying Ions

Monatomic ions are charged particles that form when a single atom gains or loses one or more electrons. An example would be Na⁺, Cl^-, Al³⁺ etc.

Polyatomic ions on the other hand are a group of atoms that carry an electrical charge. Examples include ClO₃^-, CN^- etc.

Beyond being classified as monatomic or polyatomic, an ion is also referred to as either a cation or anion.

• Cations (+) are positively charged monatomic or polyatomic ions, which have more protons than electrons.
  • Add -ion to the end of monatomic cations.
  • Ex. Sodium -> Sodium Ion, Na⁺
• Anions (-) on the other hand, are negatively charged monatomic or polyatomic ions. This means that anions have a negative charge and more electrons than protons.
  • Add -ide to end of monatomic anions.
  • Ex. Chlorine -> Chloride, Cl^-