Ionic Bonding

• Ionic bonding occurs in compounds formed from metals combined with non-metals
• In ionic bonding the particles are oppositely charged ions
• When a metal atom reacts with a non-metal atom electrons in the outer shell of the metal atom are transferred
• Metal atoms lose electrons to become positively charged ions
• Non-metal atoms gain electrons to become negatively charged ions
• The ions produced by metals in Groups 1 and 2 and by non-metals in Groups 6 and 7 have the electronic structure of a noble gas (Group 0)
• The electron transfer during the formation of an ionic compound can be represented by a dot and cross diagram


  e.g. sodium chloride

  
• An ionic compound is a giant structure of ions
• Ionic compounds are held together by strong electrostatic forces of attraction between oppositely charged ions
• Ionic compounds can be represented with a ball and stick model 


  e.g. sodium chloride

  
• Ionic compounds can be represented with a three-dimensional diagrams


  It shows the positive and negative ions

  
• The ball and stick model does not show the relative sizes of the ions and does not indicate that there are forces of attraction in all directions
• The three dimensional model of ionic compounds only shows the outer layer of the compound
• The dot and cross model does not show the structure of the compound, the size of ions or how they are arranged
• The empirical formula is the simplest whole ratio of atoms present in a compound e.g. $NaCl$,$K_2O$
• Ionic compounds have high melting and boiling points due to the strong bonds between ions
• When ionic compounds are solid they cannot conduct electricity
• When ionic compounds are dissolved or molten the ions are free to move so they can carry electric charge and conduct electricity
• Ionic compounds have regular structures (giant ionic lattices) in which there are strong electrostatic forces of attraction in all directions between oppositely charged ions