ionic bonding

• Ionic bonding

  Transfer of electrons from metals to non-metals
• Ionic compounds

  • Have high melting and boiling points
  • Have giant lattice structures
  • Have strong electrostatic forces between oppositely charged ions
  • Require a lot of heat energy to break them
• Why can't ionic compounds conduct when solid?

  1. Ions are in fixed positions

  2. Charge cannot flow
• Why can ionic compounds conduct when molten/solution?

  1. Ions are mobile

  2. Charge can flow
• Charges formed on groups of elements

  • Group 1 = +1
  • Group 2 = +2
  • Group 3 = +3
  • Group 6 = -2
  • Group 7 = -1
• Electrons


  Exist in energy levels
• Energy levels and electron capacity

  • First energy level can hold 2 electrons
  • Second and third energy levels can hold 8 electrons each
  • Fourth energy level can hold 18 electrons
• Elements in Group 0 (noble gases) have a full outer energy level
• Ionic bonding


  Occurs when elements react to achieve a full outer energy level, like the electronic structure of a noble gas
• Metals


  • Found on the left-hand side of the periodic table
• Nonmetals


  • Found on the right-hand side of the periodic table
• Ionic bonding between lithium (metal) and fluorine (nonmetal)

  1. Lithium atom loses its outer electron

  2. Fluorine atom gains the electron

  3. Both atoms now have full outer energy levels
• Lithium ion


  Atom with 3 protons and 2 electrons, resulting in a +1 overall charge
• Fluoride ion


  Atom with 9 protons and 10 electrons, resulting in a -1 overall charge
• During ionic bonding, group 1 metals lose 1 electron to form the 1+ ion, and group 7 nonmetals gain 1 electron to form the 1- ion
• Ionic bonding between sodium and chlorine

  1. 1 electron passes from sodium atom to chlorine atom

  2. Both atoms achieve a full outer energy level
• Ionic bonding


  Bonding that occurs between a metal and a non-metal, where the metal loses electrons to the non-metal
• Electron transfer in ionic bonding between group 2 metals and group 6 non-metals

  1. Group 2 metal loses 2 electrons

  2. Group 6 non-metal gains 2 electrons

  3. Produces a 2+ metal ion and a 2- non-metal ion
• Example of ionic bonding

  • Magnesium (group 2 metal) and oxygen (group 6 non-metal)
• Magnesium atom


  • 12 protons, 12 electrons (neutral)
  • Loses 2 electrons from outer shell
• Oxygen atom


  • 8 protons, 8 electrons (neutral)
  • Gains 2 electrons in outer shell
• Magnesium loses 2 electrons


  Becomes Mg2+ ion
• Oxygen gains 2 electrons

  Becomes O2- ion
• Dot and cross diagrams can be used to show ionic bonding
• Ionic bonding occurs when a metal reacts with a non-metal
• Group 2 metals lose 2 electrons to form a 2+ ion
• Group 6 non-metals gain 2 electrons to form a 2- ion