Ionic Bonding

• Ion


  An atom or molecule which has gained or lost one or more electrons
• Sodium losing an electron

  1. Sodium wants to lose an electron to have a full outer shell

  2. Chlorine wants to gain an electron to have a full outer shell

  3. Sodium gives an electron to chlorine

  4. Sodium becomes a positive ion

  5. Chlorine becomes a negative ion
• Positive ion (cation)


  An atom that has lost one or more electrons, resulting in a net positive charge
• Negative ion (anion)


  An atom that has gained one or more electrons, resulting in a net negative charge
• Ionic compound


  A compound formed by the electrostatic attraction between positive and negative ions
• Ionic compounds


  • Have a giant structure with a regular lattice of positive and negative ions
  • Millions and millions of positive and negative ions stick together
• Cation


  A positive ion
• Anion


  A negative ion
• Polyatomic ions


  • CO3 2-
  • SO4 2-
  • NO3 -
  • OH -
• Dot and cross diagram


  A diagram representing the arrangement of electrons in an atom or ion
• Strength of ionic bond

  • Depends on the charge of the ions (higher charge = stronger bond)
  • Depends on the size of the ions (smaller ions = stronger bond)
• Ions with higher charge


  Have stronger electrostatic attraction and therefore stronger ionic bonds
• Smaller ions


  Have the opposite charges closer together, resulting in stronger electrostatic attraction and stronger ionic bonds
• The strength of an ionic bond depends on the charge of the ions and the size of the ions