Cations and anions are both ions. The difference between a cation and an anion is the net electrical charge of the ion
Ions are atoms
which have gained or lost one or more valence electrons
giving the ion a net positive or negative charge.
Cations are ions with a net positive charge.
, hydronium: H3
, and ammonium: NH4+
Anions are ions with a net negative charge.
Examples: hydroxide anion: OH-
, oxide anion: O2-
, and sulfate anion: SO42-