Ionic bonding

• An ion is a charged particle formed when an atom, or group of atoms, gains or loses 1 or more electrons
• All elements in group 1 have have one electron in their outer shell. To achieve a full outer shell, they transfer this electron to another element during a chemical reaction.
• group 2 metals will lose 2 electrons to become a 2+ ion, group 3 metals will lose 3 electrons to become a 3+ ion.
• group 4 elements need to lose or gain 4 electrons to become a 4+/4- ion
• All elements in group 7 have have seven electrons in their outer shell. To achieve a full outer shell, they gain an electron from another element during a chemical reaction.
• group 6 metals will gain 2 electrons to become a 2- ion, group 5 elements will gain 3 electrons to become a 3- ion.
• In ionic bonding, electrons are transferred from the metal atom to the non-metal atom. In this process, of either losing or gaining negatively charged electrons, the reacting atoms form ions. The oppositely charged ions are attracted to each other by electrostatic forces which are the basis of the ionic bond.
• In naming ionic compounds, the metal is always named first, the non-metal second.

  The non-metals change the ending of their name when they form ions. e.g. oxygen to oxide, chlorine to chloride
• • Ionic compounds dissolve easily in water and other polar solvents
  • Ionic compounds, when in solution or molten, easily conduct electricity. They can not conduct electricity when solid, since the ions can not move
  • Ionic compounds tend to form crystalline solids with high melting temperatures
  • Ionic compounds are hard and brittle
• Physical properties of ionic compounds:

  1. high melting and boiling points - The strong bonds between the positive and negative ions mean that a huge amount of energy is needed to break the ions apart.
  2. Soluble in water - Most ionic compounds are soluble in water and form aqueous solutions. An aqueous solution is a solution in which the solvent is water.
  3. Good conductors of electricity when molten or dissolved since ions are free to move and can carry charge
• Ionic molecules are soluble in water