section_path: Modern principles/Ions and salts
section_name: Ions and salts
paragraph_text: Ions and salts
  
  An ion is a charged species, an atom or a molecule, that has lost or gained one or more electrons. When an atom loses an electron and thus has more protons than electrons, the atom is a positively charged ion or cation. When an atom gains an electron and thus has more electrons than protons, the atom is a negatively charged ion or anion. Cations and anions can form a crystalline lattice of neutral salts, such as the Na and Cl ions forming sodium chloride, or NaCl. Examples of polyatomic ions that do not split up during acid–base reactions are hydroxide (OH) and phosphate (PO).
  
  Plasma is composed of gaseous matter that has been completely ionized, usually through high temperature.